JP2003213353A - Copper alloy, production method therefor and high temperature resistant part of carburetor made of copper alloy - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a copper alloy which has remarkably improved high temperature properties such as hot forgeability, machinability, high temperature oxidation resistance and high temperature deformation resistance, and is utilized in a stable state even at high temperatures. <P>SOLUTION: The copper alloy has improved high temperature deformation resistance while maintaining its high temperature oxidation resistance by the addition of Sn and Be. The copper based alloy consists of brass at least containing, by weight, 58.5 to 62.0% Cu, 0.5 to 2.1% Sn, 0.05 to 0.1% Be and Zn, and having high temperature properties such as hot forgeability, machinability, high temperature oxidation resistance and high temperature deformation resistance. The alloy can be applied to high temperature resistant parts such as a carburetor made of a copper based alloy. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to various metal parts and products used under high temperature in the atmosphere, such as gas stove,
The present invention relates to a copper-based alloy suitable as a constituent material for a burner head, a vaporizer and nozzle of a hot oil fan heater, a mount portion of a fan heater, a method for producing the same, and a high temperature resistant component such as a vaporizer made of a copper-based alloy.

[0002]

2. Description of the Related Art Since many constituent materials such as carburetors and nozzles of this kind of oil warm air fan heater have complicated shapes, forging brass rods and free-cutting brass rods which are excellent in forgeability and machinability. However, since these constituent parts are exposed to high temperatures, problems such as poor combustion and deformation of parts have occurred. Therefore, there has been proposed a copper-based alloy made of various brass materials for improving high temperature characteristics such as hot forgeability, machinability, high temperature oxidation resistance, and high temperature deformation resistance.

For example, the copper alloy in Japanese Patent Publication No. 51-20375 has a Cu content of 63.0 to 66.0 wt.
It is a copper alloy containing 1.2 to 2.0 wt% and Ni 2.0 wt% or less. By increasing Ni content while increasing the Cu and Sn contents, the α phase is increased, and corrosion resistance and tensile strength are improved. It is intended to improve mechanical properties such as strength, elongation, proof stress and machinability. In this case, by further adding 0.1% by weight or less of Be, the alloy structure is made uniform, and it also contributes as a deoxidizing agent and a smoke preventing agent for zinc.

Japanese Patent Laid-Open No. 11-241809 discloses Sn.
Content of 0.8 to 4.0% by weight forms a Sn-containing oxide film, and reduces the deposition of CuO and ZnO on the surface of the vaporizer that is overheated to about 400 ° C. It is a vessel.

Further, Japanese Patent Laid-Open No. 2000-239763 discloses that an Al-containing oxide film is formed by including 0.3 to 2.0% by weight of Al, and the high temperature oxidation resistance and the high temperature deformation strength are improved. It is a brass alloy designed to improve.

[0006]

However, Japanese Patent Publication No. 51-20375 and Japanese Patent Application Laid-Open No. 11-241809 can improve high temperature characteristics such as high temperature oxidation resistance and high temperature deformation resistance to some extent. It is hard to say that the high temperature characteristics required for actual use can be sufficiently obtained.

Further, when Al is added as in Japanese Patent Laid-Open No. 2000-239763, not only these high temperature characteristics cannot be satisfied, but also the hot workability is remarkably deteriorated and cutting is performed. Worsen the sex,
There was a defect that the hot forgeability also deteriorated.

Further, in the above publications, when brass is used at high temperature, for example, a vaporizer made of brass is usually in a high temperature state of about 400 to 500 ° C. by a heater or the like locked to its body. Therefore, the dezincification phenomenon is likely to occur in the metal structure near the surface, and zinc oxide in which this zinc is bonded to oxygen, or an oxide such as copper oxide adheres to the surface of the vaporizer as a film. These oxide films lead to a decrease in the thermal conductivity of the carburetor body due to the heater, and also cause discoloration of the carburetor surface and peeling of the oxide film, which is not preferable in terms of appearance. Moreover, the heater locking portion of the carburetor body may be deformed due to the high temperature, and the heater may fall off from the carburetor body.

The present invention was developed in view of the above-mentioned circumstances, and its object is to significantly improve hot forgeability, machinability, and high temperature characteristics such as high temperature oxidation resistance and high temperature deformation resistance. Accordingly, it is an object of the present invention to provide a copper-based alloy that can be used in a stable state even at high temperatures, a method for producing the same, and a high-temperature resistant component such as a copper-based alloy vaporizer.

[0010]

In order to achieve the above object, the invention according to claim 1 improves the high temperature deformation resistance while adding high temperature oxidation resistance by adding Sn and Be. It is a copper-based alloy.

The invention according to claim 2 is at least Cu
58.5-62.0 wt%, Sn0.5-2.1 wt%, Be0.05-0.1 wt%, and Zn are included, and hot forgeability and machinability, especially high temperature oxidation resistance / resistance It is a copper-based alloy that is brass with excellent high-temperature characteristics such as high-temperature deformation.

According to the third aspect of the present invention, the high temperature deformation resistance is a rod shape having a supporting distance of 120 mm and a stress of 8.3 to.
It is a copper-based alloy having a characteristic that the maximum deformation amount after heating at 500 ° C. for 20 minutes under a load of 8.5 N / mm ² is 1.0 mm or less.

According to a fourth aspect of the present invention, after ingots of predetermined components are melted, they are heated to 650 to 720 ° C. and hot extruded into bars, and the bars are air-cooled to room temperature. , By heating it again at 650 to 750 ° C., then hot forging this and cutting the details,
It is a method for producing a copper-based alloy so as to produce a molded part such as a vaporizer.

The invention according to claim 5 is a vaporizer made of a copper-based alloy, which is made by using the copper-based alloy according to any one of claims 1 to 4 to manufacture parts and products such as a vaporizer. High temperature resistant parts.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a copper-based alloy, a method for producing the same, and a high temperature resistant component such as a copper-based alloy vaporizer according to the present invention will be specifically described in detail. The copper-based alloy of the present invention is a copper-based alloy having improved high temperature deformation resistance while having high temperature oxidation resistance by adding Sn and Be in the alloy,
FIG. 1 shows the relationship between the content ratios of Sn and Be of this copper-based alloy, and the range of A enclosed by the broken line is the ratio of the content of Sn and Be in the present invention. It shows the relationship.

In the same figure, the reference numeral corresponds to the number of the alloy of the present invention shown in the examples described later, and the numeral 55 shows the alloy of the comparative example. In this case, the high temperature deformation amount by the high temperature strength test in FIG. 2 described later is 0.5 mm, the high temperature deformation amount is 0.7 mm, the high temperature deformation amount is 0.9 mm, and the high temperature deformation amount is 1.0 mm. Deformation amount is 3.0m
The high temperature deformation amount of m was 3.7 mm, the high temperature deformation amount of 9.3 mm was 9.3 mm, the high temperature deformation amount was 11.2 mm, and the comparative alloy 55 was the high temperature deformation amount of 20.0 mm. And, in the case of and, the oxide film after the high temperature oxidation resistance evaluation test described later was 5 μm or less. From this relational result, the high temperature strength is improved even if the Sn content is increased without adding Be, but the effect is doubled by adding Be. That is, it has been found that a brass alloy excellent in high-temperature strength can be obtained by containing appropriate amounts of Be and Sn.

Further, as an example of the copper-based alloy in the present invention, at least Cu 58.5-62.0% by weight and S
It contains n of 0.5 to 2.1% by weight, Be of 0.05 to 0.1% by weight, and Zn, and has excellent hot forgeability and machinability, and particularly the above-mentioned high temperature oxidation resistance and high temperature deformation resistance. It is a copper-based alloy that is brass with excellent high temperature characteristics.

When a molded part is manufactured from this copper-based alloy, Cu-Sn alloy and Cu-Be alloy are used to melt ingots of predetermined components (billet or ingot), and then 650 to 720 ° C. It was heated to room temperature and hot extruded into a rod shape, which was air-cooled to room temperature, and then again
A molded part such as a vaporizer is manufactured by heating at 50 to 750 ° C., hot forging, and further cutting the details. With this manufacturing method, high-temperature oxidation resistance can be obtained by forging and cutting equivalent to general brass materials such as JIS C3771.
It is possible to obtain a molded part having excellent high temperature characteristics such as high temperature deformation resistance.

Here, each component constituting the copper-based alloy of the present invention will be described. Cu is added to improve hot workability and oxidation resistance at high temperatures. In this case, in order to obtain good hot forgeability, the addition of 58.3 to 60.0 wt% is optimal, but in order to obtain good high temperature oxidation resistance, the addition amount is increased. Is good. Considering the above characteristics, addition of 58.3 to 62.0% by weight is preferable.

Sn is added to improve the dezincing resistance and to increase the strength at high temperatures. When the added amount of Sn increases, a hard and brittle third layer, the γ layer, is deposited, which deteriorates forgeability, hot workability, and machinability. In order to obtain good strength at high temperature while having good hot workability, it is effective to add an appropriate amount of Be while suppressing the Sn content. Considering dezincification resistance and improvement of strength at high temperature, the Sn component range was set to 0.5 to 2.1% by weight. In the case of further improving hot workability and machinability, addition of 0.5 to 1.0% by weight is preferable.

Be is added in order to form a very thin and dense oxide film on the surface of the alloy when exposed to a high temperature in the atmosphere, and to prevent oxidation of the alloy base material such as dezincification. By coexisting with an appropriate amount of Sn, the strength at high temperature can be significantly improved. On the other hand, when the amount of Be added increases, the machinability and hot workability deteriorate, and the material cost increases. Therefore, the preferable Be content is 0.05
To 0.1% by weight, and when forming a denser oxide film, 0.08 to 1.0% by weight is preferable, and dezincification resistance at high temperatures can be further enhanced.

Pb is an element effective for improving the machinability and is preferably added, but its content must be suppressed in order to obtain a predetermined hot workability. Also, Pb
Is easily oxidized at high temperatures and also affects the decrease in high temperature strength. Therefore, the preferable Pb content is 1.0 to 2.5.
It was set to% by weight. Note that Bi is 0.7 instead of Pb.
~ 2.5 wt% may be added. The reason for this is B
When i is less than 0.7% by weight, the machinability deteriorates, and
When it exceeds 2.5% by weight, the tensile strength, elongation, hot forgeability, and hot workability deteriorate. Above all, in the case of brass for hot forging, if it is less than 1.0% by weight, machinability cannot be obtained, so it is preferable to set the lower limit to 1.0% by weight.

If Al is added, this Al
Is effective as an element that forms an oxide film and improves the oxidation resistance at high temperatures, but is preferably 0.05% by weight or less in order to prevent the hot workability from being significantly impaired.

The high temperature deformation resistance of the copper-based alloy according to the present invention will be specifically described. The support distance of the copper-based alloy body is 120 mm.
When evaluated by a high temperature strength test described later as shown in FIG. 2 in which the sample is heated at 500 ° C. for 20 minutes under a stress of 8.3 to 8.5 N / mm ² after heating, The amount of deformation near the center, which is the maximum amount of deformation, is 1.
It has a characteristic of 0 mm or less.

FIG. 3 is a front view showing a vaporizer using a copper-based alloy according to the present invention. 10 is a vaporizer main body, and 11 is a vaporizer main body.
Is a nozzle for ejecting fuel. A groove portion 12 for accommodating a heater (heating wire) 14 is provided in the main body 10, and an opening portion which is an accommodating port for the heater 14 is formed on the opening side of the groove portion 12.

When mounting the heater 14, the groove-shaped portion 12
With the heater 14 accommodated therein, the end portion of the opening portion is bent by means such as caulking to form a locking piece 13, and as shown in FIG. It is locked and fixed to.

[0027]

EXAMPLES Next, examples of test evaluation of the copper-based alloy according to the present invention will be described and examples will be described in detail. Example (invention alloy) No. The alloy chemical composition values of 1 to 8 are shown in Table 1,
Comparative Example No. The alloy chemical composition values of 51 to 57 are shown in Table 2, respectively.

[0028]

[Table 1]

[0029]

[Table 2]

Alloy No. of the example. 1 to 8 and alloy Nos. Of comparative examples. The ratio of the content of each Sn-Be in 55 corresponds to the circled numbers in FIG.

As the tests of Examples and Comparative Examples, tests relating to high temperature deformation resistance, high temperature oxidation resistance, hot forgeability, and machinability were conducted. Table 1 shows Examples 1 to 1.
Evaluation results in each test of No. 8, Comparative Examples 51 to 57 in Table 4
The evaluation results of each test are shown below.

[0032]

[Table 3]

[0033]

[Table 4]

Next, the test method and evaluation result of each test will be described. In FIG. 2, the schematic diagram of the high temperature strength test used for comparing the high temperature deformation resistance of an Example and a comparative example is shown. Reference numeral 15 is a test piece composed of an example or a comparative example in the present test. The test piece 15 is obtained by cutting out each alloy into a round bar having a length of 130 mm and an outer diameter of 6 mm.
Weigh 5 in the center of span B of 120 mm and weigh 0.61.
The sample was heated at 500 ° C. for 20 minutes in a heating furnace while applying a load 16 of kg and then air-cooled, and the high temperature deformation resistance was evaluated by the plastic deformation amount in the radial direction of the test piece 15 after air cooling. An example after the plastic deformation (No.
3) and a comparative example (No. 51) are shown in FIGS.
The evaluation results of this test are shown in Tables 3 and 4.

When the carburetor main body 10 of FIG. 3 is formed of a copper-based alloy made of brass, for example, when a brass material having poor high-temperature deformation resistance is used, the locking for locking the heater is performed. There is a case where the part is deformed and the state in which the heater is fixed cannot be sufficiently maintained. However, in the test result of the example, when the deformation amount is 1.0 mm or less, the usage condition is The deformation of the locking piece 13 is small, and high-temperature deformation resistance enough to endure actual use can be obtained. Therefore, in Table 3, the alloy No. 1 to 4 may be suitable for use in a vaporizer or the like, but depending on the embodiment, No. 5 to No. 8 may be used.

Next, in order to compare the high temperature oxidation resistance of the example and the comparative example, the following test was conducted and evaluated. Each material is cylindrical with an outer diameter of 30 mm and a height of 20 mm or 23 m on a side
A test piece was cut out into a hexagonal bar having a height of 20 mm and a height of 20 mm. The test piece was ground with sandpaper and a buff, heated at 500 ° C. for 500 hours in a heating furnace in the air atmosphere, and then cooled to room temperature. The high temperature oxidation resistance was evaluated based on the oxidation state of the material surface after cooling (thickness of film and presence or absence of peeling), and the results are shown in Tables 3 and 4. 8 and 9 shows 500 ° C
The conditions of the thickness of the oxide film after heating for 500 hours in Examples and Comparative Examples are shown at a photographic magnification of 200 times. In addition, in FIG. 10 and FIG.
The state of peeling of the oxide film in Examples and Comparative Examples after heating for 0 hour is shown at a photographic magnification.

In FIGS. 8 and 9, as an evaluation method, after fixing the oxidized surface of each test piece by applying a metal to the test piece, the test piece was cut with a cutting machine, and the thickness of the oxide film and the state of the structure on the cut surface were measured. I observed. In the figure, in the example, the formation of the oxide film on the alloy surface can be suppressed to be equal to or higher than that of the copper alloy containing Al (No. 53 in the comparative example).

Further, in FIGS. 10 and 11, when visually observing the appearance state of the end faces of the respective test pieces, the comparative example alloys such as Al-containing copper alloy (No. 53) showed peeling of the oxide film and Discoloration is seen. On the other hand, none of these phenomena is observed in the examples of the present invention.

Next, in order to compare the hot forgeability of the example and the comparative example, the following upset test was performed and evaluated. Each material was cut into a cylindrical shape having an outer diameter of 15 mm and a height of 15 mm to form a test piece, and the test piece was tested at a test temperature (710 ° C.,
After heating to 730 ° C, 750 ° C, 770 ° C), a predetermined upset rate (50%, 55%, 60%, 6
Compress to 5%) with a press. The hot forgeability was evaluated by the presence or absence of cracks generated on the surface of the test piece. The test results are shown in Tables 5 and 6 and FIGS. 12 and 13 for the example (No. 3) and the comparative example (No. 53), and the evaluation results are shown in Tables 3 and 4.

[0040]

[Table 5]

[0041]

[Table 6] The alloy containing aluminum (No. 53) in the comparative example has poor hot forgeability, while the examples in the present invention are J
It has the same forgeability as general brass materials such as IS C3771, and it cannot be said that there is a problem in hot forgeability.

Next, in order to compare the machinability of the present invention and the comparative material, a cutting test by the following outer diameter cutting was performed, and the machinability was evaluated by the cutting resistance generated in the work piece as a result. did. Each material has an outer diameter of 30 mm and a length of 2
The test piece cut out to a round bar of 00 mm is set on a commercially available lathe machine, the rotation speed is 1030 rpm, and the feed rate is 0.16 mm / r.
A commercially available cemented carbide tip (nose radius 0.2 mm) was used under the conditions of ev and a depth of cut of 1.5 mm for cutting. The main cutting force generated on the cutting tool during machining was measured with a strain gauge. The evaluation of machinability is No. 52 (JIS C3
The ratio of the main cutting force component in each test piece when the main cutting force component (6044) (6.44 kg) is set to 100 is shown in Tables 3 and 4 as a machinability index, and also implemented in FIGS. 14 and 15. Example (No. 3), Comparative Example (No. 51, No. 52,
No. 53, No. 56, No. 57) The fluctuation of the main component force at the time of cutting is shown.

The example is a brass for cutting, N, which is a comparative example.
o. It is possible to obtain a machinability index close to 52 and a fluctuation state of the main component force, and as can be seen from the graph of the fluctuation state of the main component force, smooth cutting can be performed.

[0044]

As is apparent from the above, according to the present invention, the hot forgeability and the machinability equivalent to those of the conventional general brass materials such as JIS C3771 and the like are 400 to 550.
At a high temperature of ℃, the formation of a dense oxide film of Be can prevent the oxide film such as zinc oxide from adhering to the surface of the alloy, and can prevent the oxide film from peeling or discoloring. It is possible to obtain a material having excellent high-temperature characteristics that achieves both characteristics of being less likely to occur.

When the alloy of the present invention is used for parts such as carburetors having protruding parts such as locking pieces, deformation of the protruding parts is small even at high temperatures, and locked parts such as heaters. The present invention is suitable for a high temperature resistant component such as a copper-based alloy vaporizer and the like, since it can be reliably locked and can sufficiently endure the use of an actual vaporizer or the like.

Further, a nozzle or the like will not be clogged due to an oxide film adhering to it, a locked component such as a heater can be securely locked, and a carburetor having excellent durability can be obtained. Therefore, it can be widely used for high temperature resistant parts such as a vaporizer made of a copper-based alloy.

[Brief description of drawings]

FIG. 1 is a graph showing a ratio of Sn and Be contents in a Goyoshi alloy according to the present invention.

FIG. 2 is a schematic diagram of a high temperature strength test in the present invention.

FIG. 3 is a front view showing a vaporizer using a copper-based alloy in another invention.

FIG. 4 is an enlarged perspective view showing the vicinity of the groove portion of FIG. 3 when the heater is locked.

FIG. 5 is an enlarged perspective view showing the vicinity of the groove portion in FIG. 3 before locking the heater.

FIG. 6 is a photograph showing the results of the high temperature strength test of the examples.

FIG. 7 is a photograph showing the results of a high temperature strength test of a comparative example.

FIG. 8 is a photograph showing the state of oxide film thickness after a high temperature oxidation test in Examples.

FIG. 9 is a photograph showing a situation of oxide film thickness after a high temperature oxidation test in a comparative example.

FIG. 10 is a photograph showing the state of oxide film peeling after the thermal oxidation test in the examples.

FIG. 11 is a photograph showing the state of oxide film peeling after a high temperature oxidation test in a comparative example.

FIG. 12 is a photograph showing the state after the upset test result of the example.

FIG. 13 is a photograph showing a state after the upset test result of a comparative example.

FIG. 14 is a graph showing how the principal component force changes during a cutting test in the examples.

FIG. 15 is a graph showing how the main component force changes during a cutting test in a comparative example.

[Explanation of symbols]

10 vaporizer body

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) C22F 1/00 650 C22F 1/00 650A

Claims (5)

[Claims] 1. A copper-based alloy characterized by having high-temperature oxidation resistance and improved high-temperature deformation resistance by adding Sn and Be. 2. At least 58.5 to 62.0 wt% Cu, 0.5 to 2.1 wt% Sn, and 0.05 to 0. Be Be.
A copper-based alloy containing 1% by weight and Zn, which is a brass excellent in high temperature characteristics such as hot forgeability, machinability, high temperature oxidation resistance and high temperature deformation resistance. 3. A support distance of 120 as high temperature deformation resistance.
A rod having a size of mm and a characteristic that the maximum deformation amount after heating at 500 ° C. for 20 minutes under a stress of 8.3 to 8.5 N / mm ² is 1.0 mm or less.
The copper-based alloy according to. 4. After smelting an ingot of predetermined components, 650
It is heated to ~ 720 ° C and hot extruded into a bar, which is air-cooled to room temperature.
Heat to 50-750 ° C, then hot forge it,
The method for producing a copper-based alloy component according to any one of claims 1 to 3, wherein a molded component such as a vaporizer is manufactured by further cutting the details. 5. A vaporizer or the like made of a copper-based alloy, characterized in that parts or products such as a vaporizer are manufactured by using the copper-based alloy according to any one of claims 1 to 4. High temperature resistant parts.