KR20010033101A - Free-cutting copper alloy - Google Patents

Abstract

The high machinability copper alloy of the present invention can secure industrially satisfactory high machinability while significantly reducing the content of zinc compared to conventional high machinability copper alloys, and is 69-79 wt% of silicon and 2.0-4.0 wt. Of silicon. % And 0.02 to 0.4% by weight of zinc, and the balance forms an alloy composed of zinc.

Description

Free Cutting Copper Alloys {FREE-CUTTING COPPER ALLOY}

Generally as a copper alloy excellent in free machinability, bronze alloys, such as JIS H5111 BC6, and brass alloys, such as JIS H3250-C3604, C3771, are known. They contain about 1.0 to 6.0% by weight of lead, which improves free machinability. Conventionally, components of various products (eg, water stoppers, water supply and drainage valves, valves, etc.) that require cutting are required. It has been used importantly.

By the way, lead is not dissolved in the matrix and is dispersed in the form of particles to improve free machinability. However, when lead content is not 1% by weight, the cut powder is as shown in Fig. 1 (D). It is created in a continuous state spirally, causing various problems such as being entangled in a bit tool. On the other hand, if the lead content is 1.0% by weight or more, the reduction of cutting resistance can be sufficiently achieved, but when the lead content is not more than 2.0% by weight, the cutting surface becomes rough. Therefore, in order to ensure industrially satisfactory high machinability, the lead content is usually set at 2.0% by weight or more. In general, about 3.0% by weight or more of lead is contained in a copper alloy extension material requiring high cutting, and about 5% by weight of lead is contained in bronze castings. For example, in the above JIS H5111 BC6, the lead content is about 5.0% by weight.

However, since lead is a harmful substance that adversely affects the human body or the environment, its use tends to be greatly limited in recent years. For example, the metal vapor generated during high temperature work such as melting or casting of alloys may contain lead components, and lead components may elute from water stoppers or valves by contact with drinking water. There is a hygiene problem. Therefore, in recent years, developed countries such as the United States tend to limit the lead content in copper alloys significantly. Therefore, there is a strong demand for development of a free cutting copper alloy in which lead content is reduced as much as possible in Korea.

The present invention relates to a free cutting copper alloy containing almost no lead component.

Fig. 1 is a sapphire stitch that shows (shows) the shape of the fin generated when the surface of the bay rod copper alloy is cut by a lathe.

The object of the present invention is to be extremely rich in free machinability despite the extremely small amount of lead (0.02 to 0.4% by weight), which is an element for improving machinability, and to be safely used as a substitute material for conventional free machinability copper alloy containing a large amount of lead. It is possible to provide a free-cutting copper alloy which is free from environmental problems including recycling of cutting powder and can cope with recent trends in which lead-containing products are regulated.

Another object of the present invention is to provide excellent corrosion resistance in addition to high machinability, cutting products, castings, cast products and the like requiring corrosion resistance (e.g., water stoppers, drainage valves, valves, stems, The present invention can be suitably used as a constituent material of hot water supply piping parts, shafts, heat exchanger parts, and the like, and is to provide a free-cutting copper alloy having a maximum practical value.

A further object of the present invention is to be excellent in high strength and wear resistance in addition to high machinability, and is required for cutting products, forgings, castings, etc. (eg, bearings, bolts, etc.) that require high strength and wear resistance. , Nuts, bushes, cog wheels, sewing machine parts, hydraulic parts, etc.), which can be suitably used, to provide a free-cutting copper alloy having a great practical value.

A further object of the present invention is to be excellent in high temperature oxidation resistance in addition to high machinability, cutting products, forgings, casting products and the like requiring high temperature oxidation resistance (e.g. nozzles for oil and gas hot air heaters, burner heads, hot water heaters). The present invention can be suitably used as a constituent member of a gas nozzle or the like, and is to provide a free-cutting copper alloy having a maximum practical value.

The present invention proposes the following high machinability copper alloy to achieve the above object.

That is, in the first invention, as a copper alloy excellent in high machinability, a high machinability containing 69 to 79 wt% of copper, 2.0 to 4.0 wt% of silicon, and 0.02 to 0.4 wt% of lead, and the remaining portion is made of zinc. We propose a Sungdong alloy (hereinafter referred to as the first invention alloy).

Lead is not dissolved in the matrix and is dispersed in the form of particles to improve the free machinability. On the other hand, silicon improves the free machinability by the appearance of the gamma phase (in this case, the κ phase) in the entire structure. As described above, the two have different functions in alloy characteristics, but they are common in terms of improving the free machinability. With this in mind, the first invention alloy enables silicon to significantly reduce lead content while ensuring industrially satisfactory high machinability. That is, the first invention alloy improves the free machinability by forming the γ phase by addition of silicon.

However, when the addition amount of silicon is less than 2.0 weight%, the gamma phase sufficient to ensure industrially satisfactory high machinability is not formed. In addition, although the free machinability improves with the increase of the silicon addition amount, even if it exceeds 4.0 weight%, there is no effect of improving the free machinability corresponding to the addition amount. However, since silicon is easily oxidized again because of its high melting point and low specific gravity, silicon is introduced into the furnace at the time of alloy melting, so that the silicon remains on the water surface, and at the same time, it is oxidized at the time of melting to become silicon oxide or silicon oxide, The production of silicon-containing alloys becomes difficult. Therefore, in the production of ingots of silicon-containing copper alloys, the addition of silicon is usually performed after the addition of Cu-Si alloys, resulting in high manufacturing costs. Even in view of such an alloy production cost, it is not preferable to add silicon beyond the amount (4.0% by weight) in which the free machinability improvement effect becomes saturated. In addition, according to the experiment, when adding 2.0 to 4.0 weight% of silicon, in order to maintain the original characteristic of a Cu-Zn type alloy, when considering the relationship with zinc content, the copper content ranges from 69 to 79 weight%. It has been found to be desirable to set as. For this reason, in the first invention alloy, the contents of copper and silicon were set to 69 to 79 wt% and 2.0 to 4.0 wt%, respectively. In addition, the addition of silicon also improves the casting property, strength, wear resistance, stress corrosion resistance, and high temperature oxidation resistance at the time of casting, in which the free machinability is improved. In addition, the ductility and dezincing corrosion resistance are also improved to some extent.

In addition, the addition amount of lead was made into 0.02-0.4 weight% for the following reason. In other words, as the first invention alloy, silicon having the same function as described above is added, so that the machinability can be ensured even if the amount of lead addition is reduced. In particular, in order to obtain the machinability superior to the conventional machinability copper alloy, Should be added at least 0.02% by weight. However, when the amount of lead addition exceeds 0.4% by weight, the cutting surface becomes rough, and workability (for example, forging) in hot is deteriorated, and ductility in cold is also reduced. If the lead addition amount is less than 0.4% by weight, it is considered that even if the lead content regulation to be enacted in advanced countries including Korea is strict, the regulation can be sufficiently passed. Also in the second to eleventh invention alloys to be described later, the amount of lead added is 0.02 to 0.4% by weight from the above reason.

In addition, in the second invention, as the copper alloy excellent in the high machinability, 69 to 79% by weight, 2.0 to 4.0% by weight of silicon, 0.02 to 0.4% by weight of lead, 0.02 to 0.4% by weight of bismuth, and 0.02 to 0.4 of tellurium A free-cutting copper alloy (hereinafter referred to as a second invention alloy) containing one element selected from the weight% and the selenium from 0.02 to 0.4% by weight and which forms the alloy composition of which the remaining part is made of zinc is proposed.

In other words, the second invention alloy forms an alloy composition in which one of the first invention alloy further contains bismuth 0.02 to 0.4% by weight, tellurium 0.02 to 0.4% by weight and selenium 0.02 to 0.4% by weight.

Bismuth, tellurium, or selenium, like lead, disperse in a matrix and disperse into particles, exhibiting a function of improving free machinability, and being capable of supplementing a shortage of lead. Therefore, when any of these is added together with silicon and lead, it becomes possible to further improve the free machinability beyond the free machinability improvement limit due to the addition of silicon and lead. As the second invention alloy, in view of these points, one of bismuth, tellurium and selenium is added to further improve the machinability in the first invention alloy. In particular, by adding bismuth, tellurium, or selenium in addition to silicon and lead, even when cutting a complicated shape at high speed, high free cutting property is exhibited. However, the free machinability improvement effect by addition of bismuth, tellurium, or selenium is not exhibited when each addition amount is less than 0.02 weight%. On the other hand, since these are more expensive than copper, even if added over 0.4% by weight, the free machinability is improved by increasing the amount of addition slightly, but the effect of the degree that is suitable for the amount of addition economically is not recognized. Moreover, when addition amount exceeds 0.4 weight%, workability in hotness (for example, forging etc.) will worsen, and workability in coldness (ductility) will also fall. In addition, even if there is a possibility that a lead-like problem may occur with respect to heavy metals such as bismuth, if there is a minor addition of 0.4% by weight or less, there is no concern that a particular problem may occur. In this regard, as the second invention alloy, the addition amount of bismuth, tellurium or selenium was 0.02 to 0.4% by weight. In addition, when lead, bismuth, tellurium, or selenium are added together, it is preferable that the total addition amount of both be 0.4% by weight or less. To be sure, if the total addition amount slightly exceeds 0.4% by weight, it is not as good as the case where the single addition amount exceeds 0.4% by weight, but the workability in hot or cold ductility starts to decrease, or the # cutting powder It is because there exists a possibility that a form may move to FIG. 1 (A) from FIG. 1 (B). , Bismuth, tellurium or selenium are the above 如 Since the free machinability is improved by a function different from silicon, the proper content of copper and silicon is not affected by these additions. Therefore, the content of copper and silicon in the second invention alloy was the same as that of the first invention alloy.

Further, in the third invention, as the copper alloy excellent in high machinability, 70 to 80 wt% of copper, 1.8 to 3.5 wt% of silicon, 0.02 to 0.4 wt% of lead, 0.3 to 3.5 wt% of rust, and 1.0 to aluminum An alloy composition containing at least one element selected from 3.5% by weight and phosphorus from 0.02 to 0.25% by weight and the remaining part is made of zinc A free cutting copper alloy (hereinafter referred to as r third invention alloy) is proposed.

When a stone is added to Cu first Zh alloy, it forms a gamma phase like silicon, and improves free machinability. For example, silicon is added by adding 1.8-4.0 weight% of stones in the Cu-Zn type alloy containing 58-70 weight% of Cu, And shows good machinability. Therefore, by adding a nephew to Cu first Si-Zn type alloy, formation of a gamma phase can be accelerated | stimulated, and the machinability of Cu first Si first Z1♀ type alloy can be improved further. It is carried out at 1.0 weight% or more, and when it reaches 3.5 weight% (needle), it becomes saturated state. Moreover, when the former addition amount exceeds 3.5 weight% (nee), not only does the formation effect of a (gamma) phase become saturated, but also ductility falls. If the amount of addition of the stone is less than 1.0% by weight, the effect of forming the γ phase is small. However, if the amount of addition of the stone is 0.3% by weight or more, the effect of dispersing and homogenizing the γ phase formed by silicon is also favorable. Machinability is improved. That is, when the addition amount of nephew is 0.3 weight% or more, the free machinability improves by the addition.

In addition, aluminum also has a function of promoting γ-phase formation like nephews, and can be further improved by adding the Cu-Si-Zn-based alloy by changing it to the same as a place or the like. In aluminum, the function of improving the free cutting property, strength, abrasion resistance, high temperature oxidation resistance and reducing the alloy specific gravity In order to exhibit the improved machinability improvement, it is necessary to add at least 1.0% by weight. However, even if it adds more than 3.5 weight%, the free machinability improvement effect suitable for the addition amount is not seen, and it causes a ductility fall similarly.

Phosphorus does not have a function of forming γ phase such as rust or aluminum, but is added by the addition of silicon or nephew and aluminum. By adding both of them together, the generated γ-phase is uniformly dispersed, and the γ-phase distribution has a good function. Thus, further improvement in free machinability due to γ-shielding can be achieved. Further, by the addition of phosphorus, if the γ phase can be dispersed at the same time as the matrix (near), the crystal grains can be refined to improve the hot-playability, thereby improving the strength and the stress corrosion cracking. Furthermore, there is also an effect of remarkably improving hot water flow during casting. The effect by such a phosphorus addition is not exhibited by addition of less than 0.02 weight%. On the other hand, when the addition amount of phosphorus exceeds 0.25% by weight (kneading), the effect of the improvement of free machinability suitable for the addition amount is not obtained, but excessive addition leads to the deterioration of the maturity and the extraction ability.

As the third invention alloy, paying attention to this point, in the Cu first Si-Pb-Zn alloy (first invention alloy), 0.3 to 3.5 pipes 196, 1.0 to 3.5% by weight of aluminum and 0.02 to 0.25% by weight of phosphorus The further improvement of free machinability is aimed at rather than adding at least one.

And 2 Nephew, aluminum or phosphorus, above 如 In order to improve free machinability by forming function of gamma phase or dispersion function of gamma phase and to improve free machinability by gamma phase, it has a close relationship with silicon. Therefore, as the third invention alloy in which rust, aluminum or phosphorus is added to silicon together, the function of improving the free machinability is exerted by replacing the hills in the silicon of the first invention alloy, thereby improving the free machinability regardless of the γ phase. Compared with the second invention alloy to which bismuth, tellurium, or selenium is added, the required amount of silicon is reduced compared to the second invention alloy which exhibits the function of making (the ability to improve the machinability by being dispersed in the form of particles in the matrix). That is, even if silicon addition amount i is less than 2.0 weight%, if it is 1.8 weight% or more, the addition of aluminum or phosphorus together can obtain the free machinability which can be industrially grooved and cracked. However, even when the addition amount of silicon is 4.02196 or less, when it exceeds 3.5% by weight (kneading), by adding nephews, aluminum, or pads together, the effect of improving the machinability by the addition of silicon becomes saturated. From this point of view, as the third invention alloy, the amount of silicon added is set to 1.8 to 3.5% by weight. In addition, from the relationship between the amount of silicon addition and the addition of stone, aluminum or phosphorus, the upper and lower limits of the copper compound 1 are determined by the second invention alloy. The preferable content was made into 70 to 80 weight%.

Further, in the fourth invention, as the copper alloy excellent in free machinability, the copper 70-80 neutral 96, the silicon 1.8-3.5% by weight, the lead 0.02-0.4% by weight 6, the rust 0.3-3.5% by weight, the aluminum 1.0- Containing at least one element selected from 3.5% by weight and phosphorus from 0.02 to 0.25% by weight and one form 9 element selected from bismuth from 0.02 to 0.4% by weight, tellurium from 0.02 to 0.43196 and from selenium from 0.02 to 0.4 垂 196 Zinc alloy composition A free cutting copper alloy (hereinafter referred to as r fourth invention alloy) is proposed.

That is, the fourth invention alloy is bismuth 0.02170.4% by weight, tellurium 0.02-0.4% by weight and selenium 0.02-0.4% by weight in the third invention alloy. The reason for the addition of these alloys, the reason for the addition thereof, and the reason for the addition amount are the same as those described for the second invention alloy.

Further, in the fifth invention, as a copper alloy excellent in corrosion resistance in addition to high machinability, it is 69 to 79 wt% copper, 2.0 to 4.0 wt% silicon, 0.02 to 0.4 wt% lead, 0.3 to 3.5 wt%, and 0.02 An alloy composition containing at least one element selected from -0.25 wt%, antimony 0.02-0.15 wt% and leather cows 0.02-: 0.15 wt% and the remaining portion is made of zinc A free cutting copper alloy (hereinafter referred to as r fifth invention alloy) is proposed.

That is, the fifth invention alloy has an alloy composition further comprising at least one of niece 0.3 to 3.5 wt%, phosphorus 0.02 to 0.25 wt%, antimony 0.02 to 0.15 wt%, and 0.02 to 0.15 wt%. will be.

Rust has a function of improving the lubrication resistance, corrosion resistance, and forging property of free machinability. In other words, the corrosion resistance of the α-phase matrix is improved, and the corrosion resistance and resistance to the dispersion of the γ-phase are improved. Stress corrosion breakage can improve the sex. As the fifth invention alloy, the corrosion resistance is improved by such a function of the stone, and the improvement of the free machinability is mainly due to the silicon addition effect. Therefore, 珪 素 及 The copper content is the same as that of the first invention alloy. On the other hand, in order to exhibit the improvement function of corrosion resistance and forging, it is necessary to make the weight of a stone at least 0.3 weight j% 6. However, even if it adds more than 3.5 weight%, the effect which improves the corrosion resistance and 鍛 1 resistance by niece addition does not acquire the effect as much as it is suitable for addition amount, and it is economically useless.

In addition, phosphorus is mentioned above By subdividing the crystal grains of the α phase in the matrix, such as by γ-phase homogenous dispersion (together), it is possible to improve the resistance to good machinability, r resistance, and anti-corrosion resistance. It is to exert the function of improving stress resistance and mechanical strength by breaking corrosion. As the fifth invention alloy, this function of an assistant is intended to improve r resistance, and the improvement of free machinability is mainly due to a silicon addition effect. The effect of improving the f-resistant resistance by the addition of the additive is exhibited by the addition of the fine 1, and is excellently selected by addition of 0.02% by weight or more. However, even if it adds exceeding 0.25 weight%, not only the moderate effect to the addition amount is acquired, but hot forging property and peeling property fall.

In addition, antimony and antimony, like phosphorus, improves 耐 脫 亞 鉛 鹿 食性 等 (not more than 0.02% by weight). However, even if it adds exceeding 0.15 weight%, not only the effect suitable for the addition amount is acquired, but also matureness and exudation property fall like the excess addition of phosphorus.

From these things, as the fifth invention alloy, if it can be placed in the first invention alloy (nee), copper, 珪 素 동 In addition to lead, by adding at least one of phosphorus, antimony, and phosphorus within the above-described range as an element of corrosion resistance, it is possible to improve not only high machinability but also corrosion resistance. In addition, in the new invention invention, the former and phosphorus do not add a free machinability improvement element other than lead of silicon and 激 1 mainly because it functions as an anticorrosive improvement element such as antimony and 砒 素. Like one invention alloy, 銅 及 The amount of silicon is 69 to 79% by weight, respectively. It exists as 2.0 to 4.0 weight%.

In addition, in the sixth invention, As the copper alloy excellent in corrosion resistance, copper 69-79: weight%, silicon 2.0-4.0 weight%, lead 0.02-0.4 weight% 96, tin 0.3-3.5 weight%, phosphorus 0.02-0.25 weight%, antimony 0.02-0.15 At least one element selected from weight% and 0.02 to 0.15 weight%, bismuth 0.02 to 0.4 weight%, tellurium 0.02 to 0.4 weight% Alloy composition composed of one element selected from Selenium 0.02-0.4 Medium 96 and the remainder part A free cutting copper alloy (hereinafter referred to as r sixth invention alloy) is proposed.

In other words, the sixth invention alloy is bismuth 0.02-0.4 wt%, tellurium 0.02-0.4 wt% and selenium 0.02-0.4 wt% To form an alloy containing one more, like the second invention alloy, 珪 素 及 Bismuth, tellurium and selenium in addition to lead The addition of one improves the free machinability, and like the fifth invention alloy, the corrosion resistance is reduced by adding at least one selected from nephew, phosphorus, antimony, and 砒 素. Thus, copper, silicon, lead, bismuth,; Tellurium The amount of selenium added is the same as that of the second invention alloy, and nephew, phosphorus and. The amount of antimony and antimony added was the same as that of the fifth invention alloy. Further, in the seventh invention, copper alloys having excellent high strength and abrasion resistance in addition to high machinability include 62 to 78 wt% of copper, 2.5 to 4.5 wt% of silicon, 0.02 to 0.4 wt% of lead, and 0.3 to 3.0 wt% of nephew. At least one element selected from 0.2 to 2.5% by weight of aluminum and from 0.02 to 0.25% by weight of phosphorus, and at least one element selected from 0.7 to 3.5% by weight of manganese and 0.7 to 3.5% by weight of nickel. This zinc alloy composition A free cutting copper alloy (hereinafter referred to as r seventh invention alloy j) is proposed.

Manganese or nickel is combined with silicon to form Mnx Siy or Nix Siy

To form a fine gold intercalation compound, and to precipitate uniformly on the matrix, thereby improving wear resistance and strength. Therefore, Man gun 及 By adding one or both of nickel l, high strength and wear resistance are improved. This effect is exerted when adding manganese and nickel 1 to each of at least 0: 7 wt%. However, even if it adds beyond 3.5 weight%, an effect becomes saturated, and the effect suitable for addition amount is not acquired. Silicon was added in an amount of 2.5 to 4.5% by weight based on the addition of manganese or nickel, taking into account the consumption 1 required for the formation of intermetallic compounds therewith.

In addition, the addition of stones, aluminum and phosphorus enhances the α phase of the matrix, thereby improving the free machinability. The nephews and neighbors improve strength and wear resistance by dispersion of the α phase and the γ phase, and also improve the free machinability. Although niece improves strength and free machinability by 0.3 weight% or more addition, when it exceeds 3.0 weight% (nee), ductility falls. Therefore, in the seventh invention alloy for improving the high strength and wear resistance, the free cutting effect was also taken into consideration, and the amount of nephew added was 0.3 to 3.0% by weight. In addition, aluminum contributes to the improvement of wear resistance, and the reinforcing function of the matrix is exhibited by addition of 0.2% by weight or more. However, when it exceeds 2.53196 (needle), ductility will fall. Therefore, the free machinability effect was also considered and the addition amount of aluminum was 0.2-2.5 Wataru196. In addition, the addition of phosphorus simultaneously disperses the γ-phase [Matri]. One grain of the α phase in [X] is refined to improve the hot-playability, and the strength and the wear resistance are also improved. Moreover, it also has the effect of remarkably improving the hot water flowing property at the time of casting. This effect is performed by adding phosphorus in the range of 0.02-0.25% by weight. In addition, about copper compound 1, it was 62 to 78 weight% from the relationship with the silicon addition amount, and the relationship with manganese and nickel 1 couple | bonded with silicon.

Furthermore, in the eighth invention, it is a copper alloy excellent in high temperature hardening resistance in addition to high machinability, with 69 to 79 wt% copper, 2.0 to 4,0 wt% silicon, 0.02 to 0.4 wt% lead, and 0.1 to 1.5 aluminum. An alloy composition containing 1% of Wataru and 0.02 to 0.25% by weight of phosphorus, and the remaining part is made of zinc A free cutting copper alloy (hereinafter referred to as "the eighth invention alloy") is proposed.

Aluminum is an element that improves strength, high machinability, and wear resistance, and is an element that improves high temperature oxidation resistance. It has the function of improving the high temperature oxidation resistance, improving the machinability, free cutting, strength, wear resistance, stress corrosion resistance. Improvement of high temperature oxidation resistance by aluminum is performed by addition of 0.1 weight% or more by addition with silicon. However, even if aluminum is added in excess of 1.5% by weight, there is no effect of improving the high temperature oxidative resistance suitable for the addition amount. In this regard, [Alminiu]. The addition amount of [non-] was 0.1-1.5 copper 1%.

Phosphorus is added to improve the flowability of hot water during alloy casting. In addition, phosphorus is added to the above-mentioned hot machinability and the above-mentioned high machinability and stiffness, and also improves high temperature oxidation resistance. Such phosphorus addition effect is exhibited at 0.02% by weight or more. However, even if it adds more than 0.25 weight%, the effect suitable for addition amount is not seen, and it is 去 1. It will lead to alloying. In this regard, the amount of phosphorus added was 0.02 to 0.25 wt%.

In addition, silicon is the above It is added to improve the free machinability, but improves the flow of hot water like phosphorus: It also has a function. The hot water flow and the improvement of the property by silicon are exhibited by addition of 2.0 weight% or more, and overlap with the addition range required for improving free machinability. Therefore, silicon addition amount was made into 2.0 to 4.0 weight% in consideration of the improvement of free machinability.

Further, in the ninth invention, as the copper alloy excellent in corrosion resistance and high temperature oxidation resistance, it is 69 to 79% by weight, 2.0 to 4.0% by weight of silicon, 0.02 to 0.4% by weight of lead, and 0.1 to 1.52196 of aluminum. , Copper alloy containing phosphorus 0.02 to 0.25% by weight, bismuth 0.02 to 0.42196, tellurium 0.02 to 0.4% by weight, and selenium 0.02 to 0.4% by weight, and the remainder being composed of zinc. r and the ninth invention alloy.

That is, the ninth invention alloy is bismuth 0.02-0.4 wt%, tellurium 0.02-0.4 wt% Selenium 0.02-0.4 wt% The alloy composition further contains By adding bismuth, which is an element that improves free machinability, such as lead, further improvement in free machinability is achieved while ensuring high temperature oxidation resistance similar to that of the eighth invention alloy.

Furthermore, in the tenth invention, as the copper alloy excellent in corrosion resistance and high temperature softening resistance, it is 69-79 wt% copper, 2.0-4.0 wt% silicon, 1 j% 6 in lead 0.02-0.4, aluminum 0.1 An alloy composition containing -1.5 wt%, phosphorus 0.02-0.25 wt%, one or more elements selected from Chrome 0.02-0.4 wt% and titanium 0.02-0.4 wt%, with the remainder being zinc A free cutting copper alloy (hereinafter referred to as r tenth invention alloy) is proposed.

Chrome and titanium have a function of improving the high temperature softening resistance, and the function is particularly exhibited by the synergistic effect of addition with aluminum. These functions are independent of adding them together (kneading) and are exhibited at 0.02% by weight or more, respectively, and become saturated at 0.:4% by weight. In view of the above, in the tenth invention alloy, the alloy composition in which the eighth invention alloy further contains at least one of Chrome 0.02 to 0.4 copper 1% and titanium 0.02 to 0.4% by weight is further developed. f It is intended to further improve high temperature oxidative property.

Further, in the eleventh invention, as the copper alloy excellent in corrosion resistance and high temperature softening resistance, copper 69-791196, silicon 2.0-4.02196, lead 0.02-0.4% by weight, aluminum 0.1-1.5% by weight, phosphorus From at least one element selected from 0.02 to 0.25% by weight, Chrome 0.02 to 0.4% and titanium 0.02 to 0.4% by weight, from bismuth 0.02 to 0.4% by weight, tellurium 0.02 to 0.4% by weight and selenium 0.02 to 0.4% by weight An alloy composition containing one selected element and the remaining part made of zinc A free cutting copper alloy (hereinafter referred to as "the eleventh invention alloy") is proposed.

That is, the eleventh invention alloy is composed of bismuth 0.02 to 0.4% by weight, tellurium 0.02 to 0.4% by weight, and selenium 0.02 to 0.4% by weight. The alloy composition containing one more thing By improving the machinability of bismuth, which is a lead-free element that improves machinability by silicon and other functions, it is intended to further improve the machinability while ensuring high temperature oxidation resistance as in the tenth invention alloy.

In addition, in the twelfth invention, the above-mentioned invention alloy, which is further improved in its machinability, is more than the heat treatment of 400 to 600 ° C. for 30 minutes to 5 hours. Alloy j).

The first to eleventh invention alloys are those containing high machinability improvement elements such as silicon,

Although it has excellent free machinability by addition of such an element, the free machinability by the function of such an added element may be improved further by heat processing. For example, the copper concentration in the first to eleventh invention alloys is high (expensive), the γ phase is small, and the crushing phase is large. The phase is changed to the γ phase, and the γ phase is finely dispersed and precipitated, resulting in excellent machinability in Kohoku. In addition, in the case of the production of actual castings, exhibitions, and mature forgings, conditions such as casting conditions, hot game processing, and productivity (working conditions) behind (hot) As a result, these ashes may be forced air cooled or water cooled. In this case, in the first to eleventh invention alloys, in particular, as the low copper concentration, the γ phase contains the β phase without being too strong, but when the heat treatment is performed (knee), the β phase becomes the γ phase by this. At the same time, the γ phase is finely dispersed and precipitated, thereby improving the free machinability. However, a few Even in the case, when the mature i treatment temperature is less than 400 ° C, the above-described phase change rate is slow, and thus it is economically ineffective because it requires extremely long time for heat treatment. Conversely (upside down), if it exceeds 600 ℃ (nee) Because a phase increases and a β phase appears,

Improvement of free machinability 效 ⊙ is not obtained. Therefore, when practicality is also considered, it is preferable to perform heat processing for 30 minutes-5 hours on conditions of 400-600 degreeC in order to improve free machinability.

As an example, ingots (shown in Tables 1 to 15) of the composition (outer diameter of 100 mm and a columnar shape of 150 mm in length) were heated to a total diameter of 15 blood m in heat (750 ° C). 1st invention alloys No.1001-No.1007, 2nd invention alloy No.2001-No.2006, 3rd invention alloy No.3001-No.3010, 4th invention alloy No.4001-No.4021, 5th invention alloy No.5001 to No.5020, 6th invention alloy No.6001 to No.6045, 7th invention alloy No.7001 to No.7029, 8th invention alloy No.8001 to No.8008, 9th invention Alloy Nos. 9001 to No. 9006, 10th invention alloys No. 10001 to No. 10008, and 11th invention alloys No. 11001 to No. 11011 were obtained. In addition, Table 16 (shown) shows that the ingot (composition of 100 mm in diameter and 150 mm in length) of the composition has been heated to the bay of 15 mm in diameter by the heated game (750 ° C). Was subjected to heat treatment under conditions indicated in Table 16, to obtain No.12001 to No.12004 of the twelfth invention. That is, No.12001 is the same composition as No.1006 of the first invention alloy. The heat treatment was carried out at 580 ℃ for 30 minutes, and No.12002 is the same as No.1006. The heat treatment was carried out at 450 ℃ and 2hrs. No.12003 is the same as No.1007 of the first invention alloy. The heat treatment was performed by heat treatment under the same conditions (580 ℃, 30 minutes) as No.12001: No.12004 is the same as No.1007. The heat treatment was performed under the same conditions (450 ℃, 2 hours) as No.12002.

In addition, as a comparative example, shown in Table 17, the ingot of the composition (circular shape of outer diameter 100 mm, length of 150 mm) was extruded between heat (750 ° C.), and the outer diameter of 15 mm was removed. (Hereinafter referred to as "r conventional alloy") Nos. 13001 to No. 13006 were obtained. No. 13001 corresponds to "Jl SC3604", No. 13002 corresponds to "CDAC36000", No.13003 corresponds to "JlSC3771", and No.13004 corresponds to rCDAC69800. . No.13005 is equivalent to "rJlSC6191", and is aluminum bronze which is excellent in strength and abrasion resistance among new products specified in Jl S. No.13006 is equivalent to rJl SC4622, and is Naval brass which is the most excellent in Zhengi province among new products prescribed by Jl S.

In order to confirm the free machinability of the first to twelfth invention alloys in comparison with the conventional alloys, the following cutting tests were carried out to determine the cutting force and the cutting powder. The cutting surface shape was determined.

In other words, the outer peripheral surface of the 各 押出 하여 obtained in the above manner was obtained by using a lathe formed by arbite + B3732 (to dig out and horns: -8.), Where: m: 50 m / minute; Pursuing Depth (Material (Value)): 1.5 mm, Spend 1: 0.11 mm / re v. The signal from the three-part dynamic dynamometer, which was cut under the conditions and established in (arbite) + B3732, was converted into a rotation signal by a weighing device, recorded in a recorder, and converted into cutting resistance. By the way,

The magnitude of the cutting force is judged by the three components, that is, the main component, the distribution, and the equal component.However, the magnitude of the cutting resistance is determined by having the principal component (N) indicating the largest value among the three components. did. The result was the way (kind) indicated by Table 18-33.

Moreover, the state of the cutting powder produced | generated by cutting is observed, and it shows (shown) to FIG. 1 (A)-(D) by the shape. It classified into four, and showed (shown) in Table 1-Table 15. By the way, 切 j shoulder, (D) is also (represented) In the case of three or more spirals, it is difficult to process the cutting powder (recovery or recycling of the cutting powder). Problems such as entanglement in the bite + B3732 or damage to the cutting surface occur, and good cutting is not possible. In addition, (C) also refers to (如) 如 In the case of a spiral shape of about two volumes from an arc shape of about half a volume, the same big problem as that of a spiral shape of three or more volumes does not occur, but the processing of cutting powder is not easy and the continuous cutting processing is not easy. In the case of, such as entanglement to bite + B3732 and the cutting surface 虞 However, in the case where the ear is yellowed in the same fine needle-like piece of (A) or the same fan-shaped piece of (B) or arc-shaped piece, Problem does not occur, and (C) and (D) point to (represent) and seem to (only) of thing It is also easy to process 切 層. However, if the thin layer (A) is melted in the same microstructure, it may infiltrate into the movement surface of a machine tool such as a lathe, causing mechanical damage, or a worker's finger or eye sticking. I have followed. Therefore, it is best to point at (B) to (above), and (A) to (show) at this point when judging high machinability, and (C) or (D) to ( It is quite improper to point out. In Tables 18-33, (B) indicates that the best 切 屈伏 態 was observed in r ◎ ', and (A) also shows (양호한) slightly good 切 j shoulder condition observed. (C) also shows (() that r is a defective r, and (D) (shows) rX is the lowest r that was observed. Pointed.

In addition, after cutting, both parts of the cutting surface were determined by surface roughening. The result was the way (kind) indicated by Table 18-33. By the way, as the basis of the surface roughness, most of the maximum height (Rolax) is used, but also based on the use of brass products, generally, R blood ax If it is 1, it can be judged that it is extremely excellent in free machinability, and 1014 blood ≤ R blood ax If it is 15 beta blood, it can be judged that the free machinability satisfactorily satisfactory was obtained, and in the case of R blood ax≥15 beta m, it can be judged that it is inferior to free machinability. In Tables 18-33, R 111 aX In the case of 104 blood, rO '', 10βm≤Rloax The case of 151βm is indicated by rΔ 'and the case of Rlllax≥154m is indicated by rX''.

From the results of the cutting test indicated in Tables 18 to 33, the first invention alloys Nos. 1001 to 1007, the second invention alloys No. 2001- No. 2006, and the third invention alloy No. 3001 to No. 3010, 4th invention alloy No. 4001 to No. 4021, 5th invention alloy No. 5001 to No. 5020, 6th invention alloy No. 6001 to N9, 6045, 7th invention alloy No. 7001 to No.7029, 8th invention alloy No.8001 to No.8008, 9th invention alloy No.9001 to No.9006, 10th invention alloy No.10001 to No.10008, 11th invention alloy No.11001 to No.11011 and No.12001 to No.12004 of the twelfth invention have the same high machinability as those of conventional alloys No.13001 to No.13003 containing a large amount of lead even in any of them. Particularly, in the state of producing the cutting powder, it is compared with the conventional alloys No.13004 to No.13006 having a lead content of 0.1% by weight or less, as well as the conventional alloy Nos. 13001 to No.13003 containing a large amount of lead. And good free machinability. In addition, the first invention alloy No.1006 Compared to No.1007, the 12th invention alloys No.12001 to No.12004 which heat-treated this had the same or more free machinability, and, depending on the conditions of alloy composition, etc., the goodness of the 1st to 11th invention alloys was achieved by heat treatment. It is understood that the machinability is further improved.

Next, in order to confirm the maturation and mechanical properties of the first to twelfth invention alloys in comparison with conventional alloys, One tension test.

That is, the first naked body of the same shape (outer diameter 15 mm, length 25 blood m) from the 各 押出 各 押 obtained as described above Book 2 test piece was taken out. And, in mature, each first test piece was heated at 700 ° C for 30 minutes, and then compressed at a compression rate of 7096 in the axial direction (the height (length) of the first test piece was 7.5 mm from 25 m blood). To the surface of the substrate (700 deg. C deformability) after visual compression was visually determined. The result was the way (kind) indicated by Table 18-33. Determination of the deformation capacity was visually determined from the state of the crack on the test piece side surface. In Tables 18 to 33, no crack was formed in rO '', small crack was formed in "△", and large crack was generated. Pointed out in rXj (shown). In addition, using each second test piece, the tensile strength test (N / mm 2) and elongation were carried out according to the kinematic method, and (96) was measured.

From the results of the maturity test and the tension test, Tables 1-33 show that the first to twelfth invention alloys are the same as the conventional alloys No.13001 to No.13004 and No.13006. It was confirmed that it has the above-mentioned maturity and mechanical properties, and can be used suitably industrially. In particular, regarding the seventh invention alloy, aluminum bronze, which is the most excellent among the new products specified in Jl S, has the mechanical properties equivalent to that of conventional alloy No.13005, and is excellent in high strength. It is understood.

In addition, the corrosion resistance and the stress corrosion cracking properties of the first to sixth invention alloys and the eighth to twelfth invention alloys are determined in accordance with the method specified in rl S 06509 to confirm the comparison with conventional alloys.試驗 れ test as specified in rJIS H3250 ”was conducted.

In other words, in the case of rl S 06509 '', the sample taken from the extraction is made so that the exposed sample surface is perpendicular to the extrusion direction of the extraction. Buried in a resin material, the surface of the sample was polished up to 1200 times with Emery paper (after), and then ultrasonically washed in pure water and dried. The obtained resultant was added to an aqueous solution (12.7 g / 1) of 1.096 cupric chloride dihydrate (CuC12 · 2H20), followed by 75 ° C. After holding for 24 hours (after), the resultant was taken out of the aqueous solution, and the maximum value (j 大 脫 亞 鉛 膚 蝕 深 요) was measured. The result was the way (kind) to show in Tables 18-25, and 28-33.

As can be understood from the results of 는 (shown in Tables 18 to 25 and Tables 28 to 33), the first to fourth invention alloys and the eighth to twelfth invention alloys, Compared with the conventional alloys Nos. 13001 to No. 13003 containing lead of large i, the fifth and sixth invention alloys having superior corrosion resistance, in particular, such as high machinability, are designed to have higher corrosion resistance. It was confirmed that it has extremely superior resistance against the conventional alloy No.13006, which is Naval brass, which is the most excellent in resistance to corrosion among the new products specified in the above.

In addition, in the stress corrosion cracking test of "JIS H3250", a sample of 150 mm in length was taken out from the spout, and each sample was placed in a state where the center part was attached to a 40 mm radius tool. The bend was made to be 45. with respect to the outer end to make a test piece. After degreasing and drying the specimens to which the tensile residual stress was applied, ammonia 券 圍 氣 (25 ° C) in [Decigeta] containing 12.596 ammonia (diluted ammonia with pure water, etc. 1) was added. I got it. That is, each specimen is held at a position approximately 80 mm above the surface of ammonia in [Decighetta]. And when the holding time in the ammonia of a test piece passed 2 hours, 8 hours, and 24 hours, the test piece was picked up from [Decigeta] and the said test piece was wash | cleaned with 1096 sulfuric acid. We acknowledged the presence or absence of cracking at a magnification boundary (magnification: 10x). The result is,

Table 1: 8, Table 25, and Tables 28-33 indicated the way (kind). In these tables, when the holding time in ammonia was 2 hours, the clear break was recognized as rXX ''. So, the break was not recognized after 2 hours, but 8 hours. In the elapsed time, when the clear break was recognized as rX, the break was not recognized in the elapsed time after 8 hours, but in the elapsed time after 24 hours, the discount is divided. れ) 認 l In r Δ j, it is indicated as “rO” for the fact that the crack is not recognized at all even after 24 hours.

As shown in Tables 18 to 25 and Tables 28 to 33, as well as the fifth and sixth invention alloys for improving corrosion resistance, such as free machinability, as understood from the results of the test, the stress corrosion is broken. Stress corrosion resistance equivalent to that of conventional alloy No.13005, which is aluminum bronze, does not contain zinc, even in the first to fourth alloys of the first to fourth invented alloys, which do not pay special attention to corrosion resistance. It was confirmed that it had the resistance to stress corrosion cracking superior to the conventional alloy No.130.06 which is Naval brass which has the property and is excellent in corrosion resistance among the new copper products prescribed | regulated to JIS.

In addition, the following oxidation test was carried out to confirm the high temperature softening resistance of the eighth to eleventh invention alloys in comparison with the conventional alloy.

That is, from No.8001 to No.8008, No.9001 to No.9006, No.10001 to No.10008, No.11001 to No.11011 及 No.13001 to 13006, the outer diameter is 14 mm Ten thousand rod-shaped test pieces were cut to have a surface cut and cut to 30 m in length so as to measure 1 of each test piece (hereinafter referred to as r softening chamber 1). After some time, it was left at 500 degreeC in the state which stored each test piece in the magnetic root whirlpool, and was left in the vaporization furnace. Then, after 100 hours have passed, the pick-up was taken from the vaporization furnace to measure 1 of each specimen (hereinafter referred to as 1 j after softening), and 1 before softening and 31 after oxidation. The softening increase1 was calculated. Herein, the term "oxidation increase 1" indicates the degree and degree of 1 (mg) during the increase due to oxidation of the surface area of the test piece 10 c blood 2 sugar, and indicates that "oxidation increase 1 (mg / 10 cm 2). ) = (Silk 1 (mg)-1 (mg) before oxidation) x (10 cm 2 / surface area of the test piece after softening (cm 2) ''

It is calculated from the equation That is, the yarn 1 after oxidation of each test piece is increasing than that before the oxidation 1, but this is due to high temperature softening. In other words, when high temperature (nee), oxygen, copper, zinc, and silicon combine to form Cu20, Zn0, and Si02, the child 1 increases due to the oxygen increase. Therefore, the degree of 1 (oxidation increase 1) of this increase was small and excellent in high temperature hardening resistance, and the results indicated in Tables 28 to 31 and 33 were shown. .

As is clear from the results of the oxidation test shown in Tables 23 to 31 and 33, the oxidization of the eighth to eleventh invention alloys is highly resistant to high temperature in the new products specified in Jl S. It is equivalent to the conventional alloy No.13005, which is aluminum bronze with chemical properties, and is much smaller than other conventional alloys, and is less than ± B. Therefore, the eighth to eleventh invention alloys are excellent in high temperature oxidation resistance in addition to high machinability. that. But it was confirmed.

In addition, as a second embodiment, the ingots (outer diameter of 100 mm and the columnar shape of length 200 mm) of the composition shown in Tables 9 to 11 (around 100 mm and a length of 200 mm) were matured (700 ° C.) with a bay diameter of 35 mm. It was added to the paste, and the seventh invention alloys No.7001a to No.7029a were obtained. In addition, as a second comparative example, shown in Table 17, the ingot of the composition (circumferential shape of 100 mm in outer diameter and 200 mm in length) was pressed out at a mature temperature (700 ° C.) to an outer diameter of 35 m blood. Nos. 13001a to No.13006a were obtained. Further, Nos. 7001 a to No. 7029 a and Nos. 1300.1 a to No. 13006 a each have the same alloy composition as those of the previously described copper alloy Nos. 7001 to No. 7029 及 No. 13001 to No. 13006. will be.

Then, the following wear test was conducted to confirm the wear resistance of the seventh invention alloy Nos. 7001a to No. 7029a in comparison with conventional alloys No.13001a to No.13006a.

In other words, from the above-mentioned cutout, the outer circumferential surface was cut, and the cut assistant test piece having an outer diameter of 32 blood m and a thickness (axial length) of 10 mm was obtained by giving a cutting process at the dawn of the hole. Each test piece is matched to a shaft which is a rotating material, and a 50 kg load is applied to the roll made of SUS304 having an outer diameter of 48 blood m in parallel with the shaft gun, and held in a state of being pressed under pressure. After a certain number of times, a roll made of SUS304 and a thickened test piece are moved at the same rotational speed (209 r.p. p.) While dropping multi oil on the outer peripheral surface of the test piece. And when the rotation speed of this test piece was set to 100,000 times, rotation of the roll made from SUS304 and the test piece was stopped, and the weight difference, ie, the wear loss (m g), before and after the rotation of each test piece was measured. Although it can be said that it is a copper alloy excellent in abrasion resistance to such an extent that abrasion reduction was small, the result was the way (kind) indicated by Table 34-36.

From the results of the abrasion test indicated in Tables 34 to 36, the seventh invention alloy Nos. 700: 1 a to No. 7029 a are conventional alloys No. 13001 to No. 13004. In addition to No.13006, it was confirmed that the wear resistance specified in Jl S was superior to conventional alloy No.13005, which is aluminum bronze, which is the most excellent in wear resistance. Therefore, in the case of comprehensively considering the results of the above-mentioned tension test, the seventh invention alloy, in addition to high machinability, has high strength and resistance equal to or higher than aluminum bronze, which is the most excellent in wear resistance among the new products specified in Jl S. It is possible to have f 를 性.

Claim

A free-cutting copper alloy comprising 69 to 79% by weight of copper, 2.0 to 4.0% by weight of silicon, and 0.02 to 0.4% by weight of lead, and further comprising an alloy composed of zinc.

1 j% 6 in 69-79, 2.0-4.0 wt% of silicon, and 0.02-0.4 in lead A high-quality cutting material comprising j% 6, bismuth 0.02-0.4% by weight, tellurium 0.02-0.4% by weight, and selenium 0.02-0.4% by weight, and the remaining part is formed of an alloy composed of zinc. Sungdong alloy.

70-80% by weight, silicon 1.8-3.5 Hiro 196, lead 0.02-0.4% by weight, rust 0.3-3.5%, aluminum 1.0-3.5% by weight and phosphorus 0.02-0.25 selected from 19% A free cutting copper alloy containing an element and further comprising an alloy composed of zinc.

One or more selected from 70 to 80 wt% copper, 1.8 to 3.5 wt% silicon, 0.02 to 0.4 wt% lead, 0.3 to 3.5 wt% copper, 1.0 to 3.5 wt% aluminum and 0.02 to 0.25 wt% phosphorus An element and a bismuth 0.02 to 0.4% by weight, tellurium 0.02 to 0.4% by weight 及 selenium containing one element selected from 0.02 to 0.4% by weight, and the remaining portion is a free-cut copper, characterized in that to form an alloy consisting of zinc alloy.

69% to 79% copper, 2.0% to 4.0% silicon, 0.02% to 0.4% lead, 0.3% to 3.53196 phosphorus, 0.02% to 0.25% phosphorus, 0.02 to 0.151196% and 0.02% to 0.15% A high machinability copper alloy containing at least one element, and further comprising an alloy composed of zinc.

69-79 wt% copper, 2.0-4.0 wt% silicon, 0.02-0.4 wt% lead, 0.3-3.5 wt% tin, 0.02-0.25 wt% phosphorus, 0.02-0.15 wt% antimony and 0.02-0.15 wt% At least one element selected from%, bismuth 0.02 to 0.4% by weight, tellurium 0.02 to 0% 4 weights 96% at least one element selected from 0.02 to 0.4% by weight, the remainder being zinc A free cutting copper alloy characterized in that the alloy composition is made.

7. Selected from 62-78 wt% copper, 2.5-4.5 wt% silicon, 0.02-0.4 wt% lead, 0.3-3.0 wt% total, 0.2-2.5 Wataru196 aluminum and 0.02-0..25 wt% phosphorous A free-cutting copper alloy containing at least one element and manganese 0.7-3.5 copper 19% nickel nickel at least one element selected from 0.7-3.5% by weight, and further comprising an alloy composed of zinc. .

8. Containing 69-79 wt% copper, 2.0-4.0 wt% silicon, 0.02-0.4 wt% lead, 0.1-1.5 wt% aluminum and 0.02-0.25 wt% phosphorus A free cutting copper alloy characterized by the above-mentioned.

9. 69-79 wt% copper, 2.0-4.0 wt% silicon, 0.02-0.4 wt% lead, 0.1-1.5 wt% aluminum, 0.02-0.25 wt% phosphorus, 0.02-0.4 wt% bismuth, Tellurium A copper alloy containing an element selected from 0.02 to 0.4% by weight 及 selenium and 0.02 to 0.4% by weight, and the remaining part of which is made of zinc.

10.69-79 wt% copper, 2.0-4.0 wt% silicon, 0.02-0.4 wt% lead, 0.1-1.5 wt% aluminum, 0.02-0.25 wt% phosphorus, 0.02-0.4 wt% chrome (B) a free-cutting copper alloy containing at least one element selected from 0.02 to 0.4% by weight of titanium, and further comprising an alloy composed of zinc.

11.69-79 wt% copper, 2.0-4.0 垂 196 silicon, 1 i% of lead 0.02-0.4, 1 j% 6 in 0.1-1.5 aluminum, phosphorus 0.02-0.25 wt%, Chrome0.02 At least one element selected from -0.4% by weight and from 0.02% to 0.4% by weight of titanium, and at least one element selected from i96, tellurium from 0.02% to 0%, 4% by weight of 4%, and from 0.02% to 0.4% by weight of selenium. A high machinability copper alloy, characterized in that the remaining portion is made of an alloy composed of zinc.

30 minutes to 5 hours at 12.400 to 600 DEG C., claim 1, claim 2, claim 3, claim 4, claim 5, claim 6, claim 7, claim 8, claim 9, claim 10 or claim 11. Free cutting copper alloy to list.

Summary

The high machinability copper alloy of the present invention can secure industrially satisfactory high machinability while significantly reducing the content of lead compared to conventional high machinability copper alloys, and is 69 to 79 wt% of silicon and 2.0 to 4.0 wt% of silicon. And 0.02 to 0.4% by weight of lead, and the alloy is composed of zinc in the remaining part.

Specification

Lead Free Copper Alloy

伎 術 分野

This invention relates to a free high machinability copper alloy containing a lead component.

Background

Generally as a copper alloy excellent in free machinability, bronze alloys, such as JIS H5111BC6, and brass alloys, such as JIS H3250-C3604, C3771, are known. These have improved lead machinability by containing about 1.0 to 6.0 weight% of lead, and ensured the machinability which can be industrially satisfied.

Since copper alloy containing lead is excellent in the above-mentioned high machinability, it is conventionally mediated as a constituent material of various products (for example, a water stopper, a water supply drainage, a valve, etc. of water supply piping). However, since lead is a toxic substance that causes harmful effects on the human body and the environment, in recent years, its use tends to be greatly limited. For example, metal vapor generated during high temperature work such as melting of alloys or castings may contain lead components, and lead components may be eluted from water stoppers or waters by contact with beverages, etc. I have an environmental hygiene problem.

Therefore, in recent years, developed countries such as the United States have tended to limit the lead content in copper alloys significantly, and in Korea, there is a strong demand for the development of roughened copper alloys in which lead content is reduced as much as possible.

Disclosure of the Invention

The object of the present invention is that, despite not containing any lead component which is a high machinability improvement element, it is extremely rich in machinability and can be used safely as a substitute material of a conventional machinability copper alloy containing a large amount of lead. Recycling, etc .: Provides lead-free copper alloys that are free from any environmental problems, including, but not limited to, recent trends in which lead-containing products are regulated.

Another object of the present invention is to provide excellent machinability in addition to high machinability, cutting products requiring corrosion resistance, 鍛 造 品, casting products and the like (for example, water plugs, water supply drainage valves, valves, stems, hot water supply piping parts) , Shafts, heat exchanger parts, etc.), which can be suitably used, and in fact, is to provide lead-free alloys with a maximum volume value.

A further object of the present invention is to be excellent in high strength and wear resistance in addition to high machinability, cutting products, forgings, castings and the like requiring high strength and wear resistance (for example, bearings, bolts, nuts, bushes, cogs, It can be suitably used as a constituent material of sewing machine parts, hydraulic parts, etc., and in fact, it is to provide a lead-free alloy for volume value improvement.

A further object of the present invention is to be excellent in high temperature oxidation resistance in addition to high machinability, cutting products, semi-finished products, casting products and the like requiring high temperature oxidation resistance (e.g. nozzles for oil and gas hot air heaters, [banar head] It can be suitably used as a constituent material of a hot water heater gas nozzle, etc., and the fact is providing a lead-free copper alloy which maximizes a volume value.

The present invention proposes the following lead-free free-cutting copper alloy to achieve the above object.

That is, in the first invention, a lead-free free-cutting copper alloy excellent in free cutting property, containing copper from 69 to 79% by weight and 2.0 to 4.:0% by weight of silicon, and further comprising zinc alloy (hereinafter, referred to as an alloy). r First invention alloy ”(d)).

Lead does not dissolve in the matrix and is dispersed in the form of particles to improve free machinability. On the other hand, silicon improves free machinability by making a (gamma phase) into a metal structure appear in a metal structure. As described above, the two have different functions in alloy characteristics, but they are common in terms of improving the free machinability. With this in mind, in the first invention alloy, by adding silicon to lead, it is not necessary to secure the free machinability that can be grooved and cracked industrially. That is, the first invention alloy improves the free machinability by forming the gamma phase by addition of silicon.

When the addition amount of silicon is less than 2.0 weight%, the gamma phase sufficient to ensure industrially satisfactory high machinability is not formed. In addition, although the free machinability improves with the increase of silicon addition 3, even if it exceeds 4.0 weight%, there is no free machinability improvement effect suitable for the addition amount. However, since silicon has a high melting point (high cost) and a low specific gravity, and is easily oxidized again, the silicon is inserted into the furnace in the furnace at the time of alloy melting, so that the silicon remains in the scene and at the time of melting Is oxidized to silicon oxide and becomes silicon oxide, making it difficult to manufacture a silicon-containing copper alloy. Therefore, in the production of ingots of silicon-containing copper alloys, silicon addition is usually performed after the Cu first Si alloy is produced, and the production [co] strike is expensive. Even in view of such an alloy production cost, it is not preferable to add silicon more than 1 (4.0% by weight) in which the free machinability improvement effect becomes saturated. According to the experiment, when silicon is added 2.0 to 4.0 copper 1% 6, the copper content is 69 to 79 when the relationship with the zinc content is also taken into consideration. It has been found to be preferred as laid out in the range of% by weight. For this reason, in the first invention alloy, the contents of copper and silicon were set to 69 to 79 wt% and 2.0 to 4.0 wt%, respectively. In addition, the addition of silicon improves the machinability and the hot water flow during casting, the strength, the wear resistance, the stress corrosion resistance, and the high temperature oxidation resistance. In addition, any benefit can be improved.

In addition, in the second invention, as a lead-free free-cutting copper alloy excellent in free machinability, it is 69-79 wt% copper, 2.0-4.0 wt% silicon, 0.02-0.4 wt% bismuth, 0.02-0.42196 and selenium 0.02 A copper alloy (hereinafter referred to as r second invention alloy j) containing at least one element selected from ˜0.4% by weight and further comprising an alloy composed of zinc is proposed.

That is, the second invention alloy is an alloy composition in which at least one of bismuth 0.02 to 0.4% by weight and tellurium 0.02 to 0.4% by weight 及 selenium 0.02 to 0.4% by weight is further contained in the first invention alloy.

Bismuth, tellurium, or selenium do not dissolve in a matrix like lead and disperse into particles, thereby exhibiting a function of improving free machinability, and improving free machinability by silicon and other functions. Therefore, when these are added together with the silicon (kneading), it becomes possible to further improve the free machinability beyond the free machinability improvement degree by the addition of silicon. As the second invention alloy, in view of this point, at least one of bismuth, tellurium and selenium is added to further improve the machinability in the first invention alloy. In particular, by adding bismuth, tellurium, or selenium in addition to silicon, even when cutting complex shapes at high speed, high roughness is exhibited. However, the free machinability improvement effect by addition of bismuth, tellurium, or selenium is not exhibited when each addition amount is less than 0.02 weight%. On the other hand, since these are more expensive than copper, even if they are added over 0.43196, the free machinability is improved in response to an increase in the amount of addition even though it is thin, but the effect that is suitable for the amount of addition economically is not recognized. Moreover, when the addition amount exceeds 0.4 weight% (needle), the workability (for example, 鍛 1 造 性 等) in matureness will fall, and workability (ductility) in cold will also fall. In addition, even if a heavy metal such as bismuth has a possibility of having a lead-like interstitial (for example), if it is a non-additive of 0.4 wt% or less, it does not go back causing a special problem. VIII: In view of these, as the second invention alloy, the addition amount of bismuth, tellurium or selenium was 0.02 to 0.4% by weight. In addition, since bismuth, tellurium, or selenium improve the free machinability by the functions different from the above-mentioned silicon | silicone, the appropriate content of 銅 及 적정 silicon is not affected by these additions. Therefore, content of copper and silicon was made the same as that of 1st invention alloy.

In addition, in the third invention, the lead-free free-cutting copper alloy excellent in free machinability similarly includes 7.0-80 wt% of copper, 1.8-3.5 wt% of silicon, 0.3-3.5 wt% of aluminum, 1.0-3.5 wt% of aluminum, and phosphorus 0.02. A copper alloy (hereinafter referred to as r third invention alloy j) containing at least one element selected from ˜0.25% by weight, and further comprising an alloy composed of zinc.

When the stone is added to the Cu-based Zn alloy, it forms a gamma phase like silicon to improve the free machinability. For example, copper is added to 1.8 to 4.0% by weight in Cu-based Zn based alloy containing 58 to 70% by weight of Cu, indicating that the metal is added and shows good machinability. Therefore, by adding stone to the Cu first Si first Zn alloy, the formation of the gamma phase can be promoted, and the free machinability of the Cu first Si first Zn alloy can be further improved. Formation of the gamma phase by a chain is performed in 1.0 weight% or more, and the toened-up state which reaches 3.5 weight% becomes. Moreover, when the addition amount of nephew exceeds 3.5 weight% (nee), not only does the formation effect of a (gamma) phase become saturated, but also ductility falls. In addition, when the nephew is less than 1.0% by weight, the formation effect of the γ phase is small, but when the addition amount is 0.3% by weight or more, it is effective to disperse and homogenize the γ phase formed by silicon. Also, the machinability is improved. That is, if the addition amount of a pipe is 0.3 weight% or more, rubbing property will improve by the addition.

In addition, aluminum also has a function of promoting γ-phase formation similarly to nephews, and, as reported, may be further added to this to further improve the free machinability of the Cu-first Si Zn-based alloy. In aluminum,

It is necessary to add at least 1.0% by weight in order to exhibit the function of improving the free cutting property, strength, abrasion resistance, high temperature oxidation resistance, and the function of reducing the alloy specific gravity and the free machinability improvement mechanism. However, even if it adds more than 3.5 weight%, the high machinability improvement effect suitable for the addition amount is not seen, and it causes a ductility fall like a nephew.

In addition, phosphorus does not have a function of forming a γ phase such as nephew or aluminum, but the γ phase produced by adding silicon or by adding both rust and aluminum together is uniformly dispersed, and There exists a function which makes a phase distribution favorable, and such a function can further improve the free machinability by gamma phase formation. In addition, by adding phosphorus, one grain of the α phase in the matrix is refined at the same time as the γ phase is dispersed, and the thermal workability is improved, and the strength and the stress corrosion are broken and the properties are also improved. Furthermore, there is also an effect of remarkably improving hot water flow during casting. Such effect by the addition is not exhibited by addition of less than 0.02% by weight. On the other hand, when the addition amount of phosphorus exceeds 0.25% by weight (knee), the effect of the improvement of free machinability suitable for the addition amount is not obtained, but excessive addition leads to the deterioration of maturity and deportability.

As the third invention alloy, paying attention to this point, rather than adding at least one of 0.3 to 3.5% by weight of tin, 1.0 to 3.5% by weight of aluminum and 0.02 to 0.25% by weight of phosphorus to the Cu-based Si-Zn alloy, The further improvement of free machinability is aimed at.

By the way, the stone, aluminum, or phosphorus improves the machinability by the above-described forming function of the γ phase or the dispersion function of the γ phase, and has a close relationship with silicon in improving the machinability by the γ phase. will be. Therefore, as the third invention alloy in which stone, aluminum, or phosphorus is added to silicon, a function of improving the free machinability is exhibited by replacing the hills with silicon of the first invention alloy, thereby improving the free machinability regardless of the γ phase. Compared with the second invention alloy to which bismuth, tellurium, or selenium is added, the required amount of silicon is reduced compared to the bismuth, tellurium, or selenium. That is, even if the silicon addition amount is less than 19% in 2.0, if it is 1.8% by weight, it is possible to obtain freely industrially satisfactory machinability by adding stone, aluminum or phosphorus together. However, even when the addition amount of silicon is 4.0% by weight or less, when it exceeds 3.5% by weight (kneading), by adding rust, aluminum, or phosphorus together, the free machinability effect of silicon addition becomes saturated. . In view of this, as the third invention alloy, the amount of silicon added is set to 1.8 to 3.53196. In addition, from the relationship between the addition amount of silicon and the addition of niece, aluminum, or phosphorus, the lower limit of the same compound 1 is slightly larger than that of the second invention alloy, and the preferred content thereof is 70% to 80%. did.

Further, in the fourth invention, as a lead-free free-cutting copper alloy excellent in free machinability, 116 in 70-80, 1.8-3.5 wt% of silicon, 0.3-3.5 wt% tin, 1.0-3.5 wt% aluminum and phosphorus 0.02 At least one element selected from -0.25% by weight, at least one element selected from bismuth 0.02-0.4% by weight, tellurium 0.02% 0.4% by weight and selenium 0.02-0.4% by weight, and the remaining part is composed of zinc Suggest a copper alloy (hereinafter referred to as r fourth invention alloy) to form an alloy.

That is, the fourth invention alloy is an alloy composition in which at least one of bismuth 0.02 to 0.4% by weight, tellurium 0.02 to 0.4% by weight and selenium 0.02 to 0.4% by weight is further contained in the third invention alloy. The reason for the determination of the amount of addition is the same as that mentioned for the second invention alloy.

In addition, in the fifth invention, the lead-free free-cutting copper alloy which is excellent in corrosion resistance in addition to high machinability, is 69-79 wt% copper, 2.0-4.0 wt% silicon, 0.3-3.5 wt%, phosphorus 0.02-0.25 wt%, A copper alloy containing one or more elements selected from 0.02 to 0.15% by weight of antimony and 砒 素 0.02 to 0.15% by weight, and the remainder of which is composed of zinc (hereinafter referred to as "the fifth invention alloy") is proposed. do.

That is, the fifth invention alloy further contains at least one of tin 0.33 to 3.5 wt%, phosphorus 0.02 to 0.25 wt%, antimony 0.02 to 0.15 wt% and 0.02 to 0.15 wt% in the first invention alloy. It is alloy composition.

The stone has a function of improving the lubrication resistance, corrosion resistance, and forging resistance of the free machinability improvement mechanism. In other words, the corrosion resistance of the α-phase matrix can be improved, and the corrosion resistance, forging resistance, and f stress corrosion resistance can be improved more than the dispersion of the γ phase. As the fifth invention alloy, the corrosion resistance is improved by such a function of nephew, and the improvement of free machinability is mainly due to the silicon addition effect. Therefore, the content of silicon and copper is the same as in the first invention alloy. On the other hand, in order to exhibit the improvement function of corrosion resistance and forging, it is necessary to make the addition amount of stone at least 0.3 weight%. However, even if it adds more than 3.5 weight%, the function which improves corrosion resistance and forging property by tin addition does not acquire the effect as much as it is suitable (the more, only), and it is economically useless.

In addition, phosphorus is finely divided by the crystal grains of the α phase in the matrix (together) to uniformly disperse the above-described γ phase γ phase, thereby improving corrosion resistance and corrosion resistance. It is to exert the function of improving the strength and mechanical strength by breaking the food, skin, and stress corrosion. As the fifth invention alloy, the phosphorus resistance is improved by this function of phosphorus, and the improvement of the free machinability is mainly due to the silicon addition effect. The effect of improving the corrosion resistance by the addition of the additive is exhibited by the addition of the fine 1, and is exhibited by addition of 0.02% by weight or more. However, even if it adds exceeding 1 j% 6 out of 0.25, a moderate effect is not acquired in addition amount, but heat-heat forging and peeling property fall rather.

In addition, antimony and acidity, like phosphorus, improves the feeding property to 1 rice 1 (0.02% by weight or more). However, even if it adds exceeding 0.15 weight%, not only the effect suitable for the addition amount is acquired, but also matureness and exudation property fall like the excess addition of phosphorus.

From these, as the fifth invention alloy, if it can be placed in the first invention alloy (kneading), it is added to copper and silicon of the same copper 1, and at least one of chromium, phosphorus, antimony and 식 as corrosion-resistant upper element within the above-mentioned range. By adding, not only the high machinability but also the corrosion resistance (等) can be improved. In addition, in the fifth invention alloy, nephew and phosphorus mainly function as an anticorrosive improvement element such as antimony and antimony, so that the first invention gold which does not add a free cutting element other than silicon and Similarly, the compound 1 of copper and silicon is as 69 to 79% by weight and 2.0 to 4.0% by weight, respectively.

Further, in the sixth invention, as a lead-free free-cutting copper alloy excellent in corrosion resistance and corrosion resistance, i 9% of copper, 69 to 79%, silicon 2.0 to 4.0% by weight, tin 0.3-3.5% by weight, At least one element selected from 0.02 to 0.25% by weight of phosphorus, 0.02 to 0.15% by weight and 0.02 to 0.15% by weight of bismuth, 0.02 to 0.4% by weight, tellurium from 0.02 to 0.4% and selenium from 0.02 to 0.4% by weight A copper alloy containing one or more elements and further comprising an alloy composed of zinc (hereinafter referred to as "sixth invention alloy") is proposed.

That is, the sixth invention alloy is an alloy composition in which at least one of the bismuth 0.02 to 0.4 and the tellurium 0.02 to 0.4 Wataru 196 及 selenium 0.02 to 0.4% by weight is further contained in the fifth invention alloy. As such, by adding at least one selected from silicon, bismuth and tellurium 及 selenium, the machinability is thus improved (together), as in the fifth invention alloy, at least selected from stone, phosphorus, antimony and 砒 素By adding one, the corrosion resistance was improved. Therefore, the addition amounts of copper, silicon, bismuth, tellurium, and selenium were the same as those of the second invention alloy, and the addition amounts of stone, phosphorus, antimony, and nickel were the same as those of the fifth invention alloy.

In addition, in the present invention, in the invention, it is a lead-free free-cutting copper alloy which is excellent in high strength and abrasion resistance in addition to high machinability, with 62 to 78% by weight of copper, 1 to 2.5% to 4.5% of copper, and 0.3 to 3.0 of tin. At least one element selected from%, from 0.2 to 2.5% by weight of aluminum and from 0.02 to 0.25% by weight of phosphorus, and at least one element selected from from 0.7 to 3.5% by weight of manganese and from 10.7 to 3.53196 of nickel. A copper alloy (hereinafter referred to as " seventh invention alloy j ") for forming an alloy is proposed.

Manganese or nickel 1 combines with silicon to form a fine metal opening compound of Mnx Siy or Nix Siy, and precipitates uniformly on the matrix, thereby improving wear resistance and strength. Therefore, by adding one or both of manganese and nickel l, high strength and wear resistance are improved. This effect is distinguished by the addition of more than 96 [u] 96 of Man gun 及 nickel Ni. However, even if it adds beyond 3.5 weight%, an effect becomes saturated, and the effect suitable for addition amount is not acquired. The silicon was added to the [oil] 96 in 2.5 to 4.5 in consideration of the consumption i required for the formation of gold compound with the addition of manganese or nickel.

In addition, the addition of stones, aluminum and phosphorus enhances the α phase of the matrix, thereby improving the free machinability.觀 及 ぴ Phosphorus improves strength and wear resistance by dispersing the α phase and the γ phase, and also improves the free machinability. The stone improves the 及 ぴ ぴ free machinability by adding 0 to 3% by weight or more, but it is added in excess of: 3.0% by weight. Therefore, in the seventh invention alloy for improving the high strength and wear resistance, the amount of addition of stone was set to 0.3 to 3.02196 in consideration of the effect of improving the machinability. In addition, aluminum contributes to the improvement of wear resistance, and the reinforcing function of the matrix is exhibited by addition of 0.2% by weight or more. However, when more than 2.5 weight% is added (needle), ductility falls. Therefore, the free machinability improvement effect was also considered and the addition amount of aluminum was 0.2 to 2.5 weight%. In addition, by the addition of scales, the crystal grains of the α phase in the matrix are refined at the same time as the γ phase is dispersed, the maturation properties are improved, and the strength and the wear resistance are also improved. Moreover, it also has the effect of remarkably improving the hot water flowing property at the time of casting.こ の よ. Moaning effect is played by adding phosphorus in the range of 0.02 to 0.25% by weight. Serrareru. In addition, as for copper compound 1, 1 及 ぴ manganese, nickel l are combined with silicon From 62 to 78 seconds 196 was set as a relationship.

In addition, according to the eighth invention, the lead-free free-cutting copper alloy excellent in corrosion resistance, high strength, and abrasion resistance is 62 to 78 wt% of copper, 2.5 to 4.5 wt% of silicon, 0.3 to 3.0 wt% of tin, and aluminum 1.0. At least one element selected from -2.5 wt% and phosphorus 0.02-0.25 wt%, at least one element selected from 0.7-3.5 wt% manganese and 0.7-3.5 wt% nickel, 19% in bismuth 0.02-0.4, A copper alloy containing one or more elements selected from 0.02 to 0.4 weight% 96 and 0.02 to 0.4 weight% of selenium, wherein the remainder is composed of zinc (hereinafter referred to as r-eighth invention alloy). Suggest.

That is, the eighth invention alloy is an alloy composition in which the seventh invention alloy further contains at least one of bismuth 0.02-0.4 medium hem 96, tellurium 0.02-0.4 wt% and selenium 0.02-0.4 wt%. By adding bismuth, which is an element which improves the machinability by other functions, and the like, a further improvement of the machinability is achieved while securing the same high strength and wear resistance as the seventh invention alloy. The reason for addition and reason for determination of the amount of addition to the high machinability improvement element such as bismuth are the same as those of the second invention alloy, the fourth invention alloy, or the sixth invention alloy. The reason for the determination of the amount of addition of the other elements (copper, zinc, stone, manganese, nickel) is the same as in the seventh invention alloy. Furthermore, in the ninth invention, it is a lead-free free-cutting copper alloy which is excellent in high temperature oxidation resistance in addition to free cutting property, and contains 69 to 79 wt% copper, 2.0 to 4.0 copper 1 j% 6, aluminum 0.1 to 1.53196, and scale 0.02. A copper alloy (hereinafter referred to as r ninth invention alloy j) containing -0.25% by weight and further comprising an alloy composed of zinc is proposed.

Aluminum improves strength, high machinability and wear resistance. It is an element that improves high temperature oxidation resistance. In addition, silicon also exhibits a function of improving high temperature oxidative resistance as described above, other to improve free-cutting property, strength, abrasion resistance, stress corrosion cracking resistance. Improvement of high temperature oxidation resistance by aluminum is performed by addition of 0.1 weight% or more by addition with silicon. However, even if aluminum is added in excess of 1.5% by weight, there is no effect of improving the high temperature oxidative resistance suitable for the addition amount. In this regard, the amount of aluminum added was 0.1 to 1.5% by weight.

Phosphorus is added to improve the flowability of hot water during alloy casting. In addition, phosphorus is added to the above-mentioned hot machinability and the above-mentioned high machinability and stiffness, and also improves high temperature oxidation resistance. Such phosphorus addition effect is exhibited at 0.02% by weight or more. However, even if it adds exceeding 0.25 weight%, the effect suitable for the addition amount is not seen, but rather, it will lead to alloying. In this regard, the amount of phosphorus added was 0.02 to 0.25 wt%.

Moreover, although silicon is added in order to improve the above-mentioned high machinability, it also has a function which improves hot water flow property like phosphorus. The hot water flow and the improvement of the property by silicon are exhibited by the addition of 19% or more of 2.0, and overlap with the addition range required for improving free machinability. Therefore, silicon addition amount was made into 0 * 4.0 weight% in consideration of the improvement of free machinability.

Further, in the tenth invention, the lead-free free-cutting copper alloy excellent in corrosion resistance and high temperature compatibility, such as 69 to 79% by weight, 2.0 to 4.0% by weight of silicon, and 0.1 to 1% by weight of aluminum, , Copper alloy containing 0.02 to 0.25% by weight of phosphorus, and at least one element selected from Chrome 0.02 to 0.43196 and titanium to 0.02 to 0.4% by weight, and the remaining part of which is composed of zinc (hereinafter r10th invention alloy j). Is suggested.

Chrome and titanium have a function of improving the high temperature oxidation resistance, and the function is particularly exhibited by the synergistic effect of addition with aluminum. These functions are independent of adding them together (kneading) and are exhibited at 0.02% by weight or more, respectively, and become saturated at 0.4% by weight. In view of the above, in the tenth invention alloy, the alloy composition in which at least one of the chromium 0.02 to 0.4% by weight and the titanium 0.02 to 0.4% by weight is further contained in the ninth invention alloy, the high temperature of the ninth invention alloy It is trying to further improve softening.

In the eleventh invention, as a lead-free free-cutting copper alloy excellent in corrosion resistance and high temperature oxidation resistance, it is 69 to 79% by weight, 2.0 to 4.0% by weight of silicon, 0.1 to 1% by weight of aluminum, 1% phosphorus 0.02-0.25 copper, at least one element selected from bismuth 0.02-0.4% by weight, tellurium 0.02-0.4% by weight 及 selenium 0.02-0.4% by weight, and the remaining portion is composed of zinc We propose a copper alloy (hereinafter referred to as r eleventh alloy j).

That is, the eleventh invention alloy is an alloy composition in which the ninth invention alloy further contains at least one of t96 in bismuth 0.02 to 0.4 and tellurium 0.02 to 0.4% by weight 중량 selenium 0.02 to 0.4 11% 6.如 く By adding bismuth, which is an element exhibiting high machinability by silicon and other functions, it is intended to improve the high machinability while ensuring high temperature oxidation resistance like the ninth invention alloy.

In the twelfth invention, the lead-free copper alloy, which is excellent in corrosion resistance and high temperature oxidation resistance, is 69-79 wt% copper, 2.0-4.0 wt% silicon, 296 in aluminum 0.1-1.5, and phosphorus. At least one element selected from 0.02 to 0.25% by weight, Chrome 0.02 to 0.4% and titanium 0.02 to 0.4% by weight, bismuth 0.02 to 0.4% by weight, tellurium 0.02 to 0.4% by weight 及 selenium 0.02 to 0.4% by weight A copper alloy containing one or more elements selected from the above and further comprising an alloy composed of zinc (hereinafter referred to as r twelfth invention alloy) is proposed.

That is, the twelfth invention alloy is an alloy composition in which at least one of bismuth 0.02 to 0.4% by weight, tellurium 0.02 to 0.4% by weight and selenium 0.02 to 0.4% by weight is further contained in the tenth invention alloy. By adding bismuth, which is an element that improves the free machinability by other functions, and further improving the free machinability while ensuring high temperature hardening resistance similar to that of the tenth invention alloy.

In addition, in the thirteenth invention, the lead-free machinability copper alloy (hereinafter referred to as the r thirteenth invention alloy) further improved the free machinability than the heat treatment for 400 minutes to 400 ° C for 30 minutes to 5 hours. J).

The first to twelfth invented alloys are those having added high machinability improvement elements such as silicon, and having excellent machinability by the addition of such elements, but especially having high copper concentrations (expensive), α, β, γ, 6 In the case where there are many phases other than phases (phases which are not mainly), the N phase is phase-changed by the heat treatment, and the γ phase is finely dispersed and precipitated, whereby the free machinability is further improved. For example, as the cost is high,

Although the ductility of the matrix is high and the absolute amount of the γ-phase is small, it is excellent in cold workability. However, when cold-cooling and cutting processing such as Kajime are required, the above-described bonds are extremely effective. In other words, when the copper concentration in the first twelfth invention alloy is high (expensive), the γ phase is small and the [bar] phase is large (hereinafter referred to as r copper concentration alloy j), り り り 상 is different. By changing the γ phase and finely dispersing and depositing the γ phase, the free machinability is further improved. In addition, in the case of the production of the real casting, the exhibition, the mature product, the conditions such as the casting condition, the productivity after the mature production, the working environment, etc. As a result, these ashes may be forced air cooled or water cooled. In this case, in the first to twelfth inventions, in the case of low Q (hereinafter referred to as r 低 銅 獲 度 合金), the γ phase slightly contains β phase, but is subjected to heat treatment. (K) By this, the β phase is changed to the γ phase and the γ phase is finely dispersed and precipitated: The free machinability is improved. As a result of the experiment, the compounding ratio of 銅 及 ぴ silicon and other additive elements (except zinc) A is 67 ≦ Cu 13 Si + a A, and the composition of high 銅 囊 度 合金 or 64≥Cu In low copper concentration alloys having a composition of 13 Si + a A, the effect of heat treatment is particularly remarkable. In addition, a is a coefficient different according to the additive element A, for example, nephew: a = 10.5, aluminum: a = 12, phosphorus: a = 13, antimony: a = 0, = 0: a = 0, manganese: a = + 2.5, nickel l: a = + 2.5.

However, even in some cases, if the heat treatment temperature is 400 ° C., the above-described phase change rate is slow, and therefore it is not practical for economic 25, because it requires a very long time. On the contrary (inverted), if it exceeds 600 ° C (ni), the effect of improving the machinability is not obtained because the phase of the phase increases and the β phase appears. Therefore, when practicality is also considered, it is preferable to perform heat processing for 30 minutes-5 hours on 400-600 degreeC condition for free machinability improvement.

Drawing brief description

Fig. 1 is a sloping cross section that shows (shows) the shape of the cutting powder produced when the surface of a ten thousand long copper alloy is cut by a lathe.

Example

As an example, ingots (shown in Tables 1 to 35) of the composition (circumferential shape of 100 mm in outer diameter and 150 mm in length) were grown to a rod of 10,000 mm in outer diameter 15 mm with mature 間 (750 ° C). , 1st invention alloy No.1001-No.1008, 2nd invention alloy No.2001-No.2011, 3rd invention alloy No.3001l No.3012, 4th invention alloy No.4001-No.4049, 5th Invention Alloys No. 5001 to No. 5020, 6th Invention Alloy No. 6001 to No. 6105, 7th Invention Alloy No. 7001 to No. 7030, 8th Invention Alloy No. 8001 to No.8147, 9th Invention Alloy No.90011 No.9005, No. 10 Invention Alloy No. 10001 to No. 10008, No. 11 Invention Alloy No. 11001 to No. 11007 and No. 12 Invention Alloy No. 1200.1 to No. 12021 were obtained. In addition, Table 36 shows the ingot of the composition (outer diameter of 100 mm, columnar shape of 150 blood m in length) with a mature 押 (750 ° C) in a bay with an outer diameter of 15 mm. The heat treatment was conducted under conditions indicated in Table 36 (shown in Table 36) to obtain the thirteenth invention alloys No.13001 to No.13006. That is, No. 13001 is heat-treated with the same composition as No. 1005 of the first invention alloy at 580 ° C for 30 minutes, and No. 13002 is the same composition as No. 13001 with 450 ° C and 2 It was heat-treated under the condition of time, and No.13003 was matured under the same composition as No.1007 of the first invention alloy at 580 ° C (30 minutes) under No.13001, and No.13004 was No. The same composition as No.13002 is heat-treated under the same conditions as No.13002 (450 ℃, 2 hours) .No.13005 is the same as No.1008 in the first invention alloy No.13001 is the same as No.13001. Heat treatment was carried out under the condition (580 ° C., 30 minutes), and No. 1§006 was heat-treated under the same conditions as No. 13002 under the same conditions as No. 13002 (450 ° C., 2 hours).

In addition, as a comparative example, the ingot i of the composition shown in Table 37 (outer diameter 100 mm, columnar shape of 150 mm length) was extruded at a temperature between 750 ° C. to produce a bay of 15 mm outside diameter.材 (hereinafter referred to as r conventional alloy) No.14001 to No.14006 were obtained. No.14001 corresponds to "Jl SC3604j, No.14002 corresponds to rCDAC36000j, No.14003 corresponds to rJl SC3771j, and No.14004 corresponds to rCDAC69800. No.14005 is equivalent to rJl SC6191j, and is an aluminum bronze that is most excellent in steel plate and wear resistance among new products specified in Jl S. No.14006 is equivalent to "rJl SC4622", and is Naval bronze which is the most excellent in endurance among the new products specified in Jl S.

In order to confirm the free machinability of the first to thirteenth invention alloys in comparison with conventional alloys, the following cutting tests were conducted to determine cutting principal force, 切 l shoulder state, and cutting surface shape.

That is, a cutting speed of 50 m / min was determined by a lathe in which the outer circumferential surface of the spout obtained as described above was obtained by arbite + B3732 (spurted) and horns (18) were formed. Depth (cut): 1.5 mm, cut under conditions of 1: 0.11 mm / re: v., And weigh the signal from a three-part dynamic dynamometer established at (arbite) + B3732. It was converted into a recorder by a recorder, recorded by a recorder, and converted into cutting resistance. By the way,

The magnitude of the cutting force is judged by the three components, that is, the main component and the equal distribution, but here, the largest component among the three components has the main component (N). I did it. The result was the way (kind) indicated by Table 38-66.

In addition, the state of the j j layer formed by cutting was observed, and the shape (see) shown in Figs. 1 (A) to (D) was classified into four according to the shape, and shown in Tables 1 to 37 (shown in Table 1). Pointed. By the way, 切 j shoulder, (D) is also visible ()), if you have three or more spirals, the processing of cutting powder (recovering and recycling of 切 居: 等 十 棚 困 離) In this case, problems such as cutting powder may become entangled in the bite + B3732, damage to the cutting surface, etc., resulting in a poor cutting process, as shown in (C). If you are in the shape of a spiral of about two volumes from a circular arc shape of around half a circle, the same big problem does not occur when you have three or more spirals, but it is not easy to process the cutting powder. In the case of continuous cutting, the leather re が ア ル which produces bite to the bite + B3732 and the edge of the cutting surface.However, the same fine needle-like piece of (Å) The same fan-shaped or arc-shaped pieces of B) It is not easy to have such problems as above in reru 犧 合, and (C) and (D) are easy to see because they do not seem to stretch out like thing of (thing), too. However, in the same way, the A (A) also leaves the momentum in the same shape, and the mechanical interference is inserted into the surface of the machine tool such as a lathe, causing mechanical failure: Therefore, it is best to point at (B) to (show) and (A) to (see) at this point when judging high machinability. It is appropriate to point to (shown) in (D) or (D) .In Tables 38 to 66, (B) refers to (B). The good quality was observed in r ◎ '', and (A) also showed slightly good cutting powder 狀態. In rOj, (C) also showed poor quality. In rΔj, (D) points to (rx) that the most significant magnitude is observed.

In addition, after cutting, both parts of the cutting surface were determined by surface roughening. The result was the way (kind) indicated by Table 38-66. By the way, as the standard of the surface roughness, the maximum height (R blood ax) is mostly used depending on the use of brass products, but in general, it can be judged that Rmax of 104 m is extremely excellent in excellent machinability. When 104 m ≤ Rmax * 151βm, it can be judged that industrially satisfactory high machinability was obtained. In the case of Rnlax≥151βm, it can be determined that the machinability is inferior to high machinability. In Tables 38 to 65, the case of Rolax 104 blood is shown as rO ", the case of 10βm≤R blood ax * 1514 m is represented by rΔ", and the case of Rlllax≥151 [bar] n is represented by rX "( Pointed.

From the results of the cutting test indicated in Tables 38 to 66, the first invention alloys No. 1001 to No. 1008, the second invention alloys No. 2001 to No. 2011, and the third invention alloy are shown. No.3001-. No.3012, 4th invention alloy No.4001-No.4049, 5th invention alloy No.5001-No.5020, 6th invention alloy No.6001-No.6105, 7th invention alloy No.7001-No. 7030, 8th invention alloy No.8001 to 88147, 9th invention alloy No.9001 to No.9005, 10th invention alloy No.10001 to No.10008, 11th invention alloy No.11001 to No.11007 And the twelfth invention alloys No.12001 to No.12021 have the same high machinability as those of the conventional alloys No.14001 to No.14003 containing a large amount of lead even in any of them. Particularly, conventional alloy No.14001 containing a large amount of lead as well as non-alloy No.14004 to No.14006 due to the fact that lead content is less than 0.1% by weight in the state of formation of iron. Even if compared with -No.14003, it has favorable free machinability.

Further, as is apparent from Tables 38 and 65, the thirteenth invention alloys No. 13001 to No. 13006 were compared with the first invention alloys No. 1005, No. 1007 and No. 1008 which have the same composition as these. Free machinability was improved, and it was confirmed that free machinability was further improved by giving appropriate heat treatment.

Next, the following tensile strength test was conducted to confirm the mature mechanical properties of the first to thirteenth invention alloys in comparison with conventional alloys.

That is, the first and second test pieces of the same shape (outer diameter 15 mm, length 25 mm) were taken out from the spouts obtained as described above. In the thermocompression test, each first test piece was heated at 700 ° C. for 30 minutes,

. Compression was carried out at a compression rate of 709% in the axial direction (compression until the height (length) of the first test piece became 7.5 mm at 25 m), and visually determined the surface shape (after 700 ° C deformation) after compression. . The result was the way (kind) indicated by Table 38-66. Determination of the deformation capacity was visually determined from the state of cracks on the test piece side surface, and in Tables 38 to 66, no cracks occurred. So a small crack has occurred in rΔ j and a large crack has occurred in rXj (shown). In addition, using each second test piece, the tensile strength test (N / m m 2) and elongation were carried out according to the kinematic method, and (96) was measured.

From the results of the maturity test and the tensile strength test, Tables 1 to 13 show that the first to thirteenth invention alloys are the same as conventional alloys No.14001 to No.14004 and No.14006. It was confirmed that it had the above maturity and mechanical property, and was able to use industrially suitably. In particular, with regard to the seventh and eighth invention alloys, It is understood to have the same mechanical properties as those of conventional alloy No. 14405, which is also excellent aluminum bronze, and excellent in high strength.

In addition, the corrosion resistance of the first to sixth alloys of the first to sixth metal alloys, the stress corrosion resistance and the corrosion resistance of the alloys are determined by the method specified in rl S 06509 j so as to confirm the cracking resistance in comparison with conventional alloys. The stress corrosion cracking test prescribed | regulated to X and "JIS H3250" was done.

That is, in the case of rl S 06509 ", the sample taken from the 各 押出 材 is placed so that the surface of the [dew] sample is perpendicular to the extrusion direction of the 當 該 押出 材. The surface of the sample was polished up to 1200 times with Emery paper (after), and then ultrasonically cleaned in pure water and dried. Thus obtained skin food sample was subjected to Nagahama in an aqueous solution (12.7 g / 1) of 1.0 j% 6 cupric chloride dihydrochloride (CuC12.2H20), under a temperature condition of 75 ° C (bottom). After holding for 24 hours (after), the solution was taken out of an aqueous solution and the maximum value was measured. The result was the way (kind) which points to Table 38-Table 50, and Table 61-Table 66 (shown).

As shown in Tables 38 to 50 and Tables 61 to 66, the first to fourth alloys of the 9th to 13th invention alloys are Is superior to the conventional alloys No.14001 to No.14003 containing a large amount of lead. [Secondary] The corrosion resistance of the second and sixth invention alloys, in particular, to improve the corrosion resistance, such as high machinability, is Jl. It was confirmed that it has extremely excellent corrosion resistance compared to the conventional alloy No.14006 which is Naval brass which is the most excellent in corrosion resistance among the new products prescribed by S.

In addition, in the J れ test of rJIS H3250j, a 150-meter-long blood sample was taken out from the 各 押出 材, and each sample was put in the center of a 40-mm radius 그 治 具, One end was deposited so as to be 45. with respect to the outer end of the test piece. In this way, degreasing each specimen to which tensile residual stress is applied. After drying, it was held in an ammonia atmosphere (25 占 폚) in [Decigeta] containing 12.596 ammonia (diluted ammonia with pure water such as 1). That is, each specimen is held at a position of about 80 m above the ammonia surface in [Decighetta]. Then, when the holding time in the ammonia of the test piece passed 2 hours, 8 hours, and 24 hours, the test piece was picked up from [Decigeta] and washed with 1096 kPa. The presence or absence of the fracture of the test piece was recognized by the magnification boundary (magnification: 10 times). The result is,

Tables 38-50 and Tables 61-66 point to (show) the way (kind). In these tables, when the holding time in ammonia was 2 hours, the clear break was recognized in rXXj, but the break was not recognized in 2 hours, but 8 hours passed. For the time when clear break was recognized in the time, "x" was regarded as being broken. In 8 hours, the break was not recognized, but the clear break was recognized in 24 hours. In r Δ j, it is indicated as “0” (not shown) regarding the fact that the crack is not recognized at all even after elapse of 24 hours.

As shown in Tables 38 to 50 and Tables 61 to 66, as well as the fifth and sixth invention alloys for improving the corrosion resistance, such as free machinability, as understood from the results of the test, the stress corrosion is broken. In the first to fourth invention alloys and the ninth to thirteenth invention alloys, which do not pay special attention to corrosion resistance, they have stress corrosion resistance that is equivalent to that of conventional alloy 14005, which is aluminum bronze, which does not contain zinc. , It was confirmed that among new products specified in Jl S, it has superior 耐 應 力 魔 蝕 割 れ resistance than conventional alloy No.14006, which is Naval brass which is the most excellent in corrosion resistance.

In addition, the following oxidation test was carried out to confirm the high temperature oxidation resistance of the ninth to twelfth invention alloys in comparison with the conventional alloy.

That is, from No.9001 to No.9005, No.10001 to No.10008, No.11001 to No.11007, No.12001 to No.12021 及 No.14001 to 14006, the outer diameter is 14 mm Ten thousand rod-shaped specimens were obtained by surface attenuation and cut into 30 m blood to measure the length of each specimen (hereinafter referred to as r before oxidation). . Each test piece was left in the electric furnace hold | maintained at 500 degreeC in the state which stored in 磁性 after some (after scolding). And after picking up from the electric furnace when 100 hours passed, and measuring the child 1 (hereinafter referred to as "1 after r oxidation") of each test piece, before 31 oxidation and after oxidation 1 and か ら softening increase1 were calculated. Here, the oxidation increase 1 indicates the degree of 1 (p g) of the increase by the oxidation of the surface area of the test piece 10 c blood 2 sugar, and the r oxidation increase 1 (p g / 10 c blood 2). ) = (Post Oxidation Thread 1 (mg) 1 Preoxidation Chamber 1 (mg)) x (10 cm 2 / Surface Area of the Test Piece (cm 2) '', that is, the thread 1 after oxidation of each test piece is oxidized. Although it is increasing than the total weight, it is due to high temperature oxidation, that is, when high temperature (nee) bonds with oxygen, copper, zinc, and silicon, Cu20, Zn 0, and Si. The increase in oxygen is increased by 1, so that the degree of 1 (oxidation increase 1) is small and excellent in high temperature oxidation resistance. Resulted in (shown).

As shown in Table 61 to Table 64 and Table 66 (as shown), the increase in redness of the ninth to twelfth invented alloys is high within the new products specified in J-IS, as is apparent from the results of the oxidation test. It is equivalent to conventional alloy No.14005, which is bronze having an oxidizing property, and is extremely small than other conventional alloys. therefore,

. It was confirmed that the ninth to twelfth invention alloys were excellent in high temperature oxidation resistance in addition to the free cutting property.

In addition, as a second embodiment, the ingots (outer diameter of 100 mm and the columnar shape of length 200 mm) of the composition shown in Tables 14 to 31 (a column of 100 mm in diameter and 200 mm in length) were obtained in a mature bar (700 ° C.) with a bay bar of 35 mm in outer diameter. The seventh invention alloys No.7001a to No.7030a and the eighth invention alloys No.8001a to No.8147a were obtained. In addition, as a second comparative example, shown in Table 37, the ingot of the composition (outer diameter of 100 mm and the length of 200 mm) was extruded at a mature temperature (700 ° C.) to an outer diameter of 35 mm. Only a rod-shaped extruded material (hereinafter referred to as "r conventional alloy") No.14001a to No.14006a were obtained. No.7001 a to No.7030 a and N..8001 a to N .. 8147 a stripped N..14001 a to N..14006 a are copper alloys No.7001 to No.7030, respectively. The same alloy composition as in N9,8001 to No.8147 and No.14001 to No.14.006 is performed.

And the wear resistance of 7th invention alloy No.7001a-No.7030: a and 8th invention alloy No.8001a -No.8147a was confirmed by the comparison with alloy No.14001a-No.14006a. To do this, the following abrasion test was carried out.

That is, from each extruded material obtained as described above, after cutting the outer circumferential surface thereof, the ring-long test piece having an outer diameter of 32 m blood and a thickness (axial length) of 10 mm m was obtained by cutting the hole circumference and cutting. The test piece is fitted to the shaft which is a rotating material, and it is held in a state of being pressed into a roll of 50 kg of SUS304 having an outer diameter of 50 mm (parallel) in parallel with the axis. After what (backing up),

A roll made of SUS304 and the adjacent test piece are rotated at the same rotational speed (20 g r.p.m.) while dropping multi oil on the outer peripheral surface of the test piece. When the rotation speed of the test piece reached 100,000 times, the rotation of the roll made of SUS304 and the test piece was stopped, and 1 (m g) was measured to reduce the middle order, that is, the wear, before and after the rotation of each test piece. Although it can be said that it is the copper alloy excellent in abrasion resistance to such an extent that abrasion reduction was small, the result was the way (kind) shown to Table 67-77. From the results of the abrasion test indicated in Tables 67 to 77, the seventh invention alloys No.7001 a to No.7030 a and the eighth invention alloy Nos. 8001 a to No.8147 a are Compared with the conventional alloys Nos. 14001 to No. 14004 and No. 14005, the aluminum bronze is excellent in wear resistance among the new products specified in JS. It was confirmed that it is excellent in abrasion resistance even compared with the conventional alloy No.14005. Therefore, when comprehensively considering the results of the above-mentioned tension test, the seventh and eighth invented alloys, in addition to the high machinability, have a high strength equal to or higher than that of aluminum bronze, which is the most excellent in abrasion resistance among the new products specified in Jl S. It has sex and wear resistance. It can be said.

Claims (12)

A lead-free free-cutting copper alloy containing 9% of copper from 69 to 79 and from 2.0 to 4.0% by weight of silicon, and the remainder of which is made of zinc. 69-79 wt% of silicon, 2.0-4.0 wt% of silicon, 0.02-0.4 wt% of bismuth, 19% of tellurium 0.02-0.4, and at least one element selected from 0.02-0.4 wt% of selenium; A lead-free free-cutting copper alloy characterized in that the alloy is made of zinc. 70 to 80% by weight, 5 to 5% by weight of silicon, 1.8 to 3%, and one or more elements selected from 0.3 to 3.5% by weight, 1.0 to 3.5% by weight of aluminum, and 0.02 to 0.25% by weight of phosphorus. A lead-free free cutting copper alloy, characterized in that the portion is made of an alloy consisting of zinc. At least one element selected from 70 to 80% by weight of copper, 1.8 to 3.5% by weight of silicon, 0.3 to 3.5% by weight of green, 1.0 to 3.53196 of aluminum and 0.02 to 0.25% by weight of phosphorus, 0.02-0.4% by weight of bismuth, and A lead-free free-cutting copper alloy containing at least one element selected from tellurium from 0.02 to 0.4% by weight and selenium from 0.02 to 0.4% by weight, and the remainder being composed of an alloy composed of zinc. 1 type selected from 69-79 weight% of copper, 2.0-4.0 weight% of silicon, i96, phosphorus 0.02-0.25 weight 96, antimony 0.02-0.15 weight 9% in all 0.313.5, and 0.02-0.15 weight of silicon. A lead-free ductile copper alloy containing the above elements, wherein the remaining portion is zinc to alloy composition. At least one element selected from 69 to 79 weight percent copper, 2.0 to 4.0 weight percent silicon, 0.3 to 3.5 weight percent rust, 0.02 to 0.25 weight percent phosphorus, 0.02 to 0.15 weight percent antimony, and 0.02 to 0.15 weight percent arsenic; Lead-free free-cutting copper alloy containing at least one element selected from bismuth 0.02 to 0.4% by weight, tellurium 0.02 to 0.4% by weight and selenium 0.02 to 0.4 by weight, and the remainder being composed of zinc. . At least one element selected from 62 to 78 weight percent copper, 2.5 to 4.5 weight percent silicon, 0.3 to 3.0 weight percent tin, 11 to 6 weight percent 0.2 to 2.5 aluminum and 0.02 to 0.25 weight percent phosphorus, manganese 0.7 to 3.5 A lead-free free-cutting copper alloy containing at least one element selected from weight% and nickel 0.7-3.5% by weight, and further comprising an alloy composed of zinc. 62-78 weight% of copper, 2.5-4.5 weight% of silicon, 0.3-3.0 weight% of tin, 0.2-2.5 weight% of aluminum, and 0.02-0.25 weight% of phosphorus, and manganese 0.7-3.5 weight% And at least one element selected from nickel 0.7-3.5 wt% nickel, and at least one element selected from bismuth 0.02-0.4 wt%, tellurium 0.02-0.4 wt% and selenium 0.02-0.4 wt% A lead-free free-cutting copper alloy characterized in that the alloy is made of zinc. Lead-free free cutting comprising 69 to 79 wt% of copper, 2.0 to 4.0 wt% of silicon, 0.1 to 1.5 wt% of aluminum, and 0.02 to 0.25 wt% of phosphorus, and further comprising an alloy composed of zinc. Sungdong alloy. From 69 to 79 wt% of copper, 2.0 to 4.0 wt% of silicon, 0.1 to 1.5 wt% of aluminum, 0.02 to 0.25 wt% of phosphorus, 0.02 to 0.4 wt% of chromium, and 0.02 to 0.4 wt% of titanium. A lead-free free-cutting copper alloy containing at least one selected element, and further comprising an alloy composed of zinc. 69-79 wt% of copper, 2.0-4.0 wt% of silicon, 0.02-0.4 wt% of zinc, 0.1-1.5 wt% of aluminum, 0.02-0.25 wt% of phosphorus, 0.02-0.4 wt% of chromium and 0.02--titanium A free-cutting copper alloy comprising an alloy composition comprising 0.4% by weight, 0.02% to 0.4% by weight and 0.2% to 0.4% by weight of selenium. The method according to claim 1, 2, 3, 4, 5, 6, 7, 7, 8, 9, 10, or 11, which is 400 to 600 ° C. A free cutting copper alloy which has been heat treated for 30 minutes to 5 hours.