TW201107500A - Low-lead copper alloy - Google Patents

Abstract

This invention relates to a low-lead copper alloy comprising: 0.05-0.3 wt% of lead, 0.3-0.8 wt% of aluminum, 0.01-0.4 wt% of bismuth, 0.1-2 wt% of nickel, and 96.5 wt% and more of copper and zinc, wherein the copper is 58-70 wt% of the low-lead copper alloy. The low-lead copper alloy of the present invention provides excellent material properties, good tenacity and processing properties, and has improved alloy strength and corrosive resistance.

Description

201107500 VI. Description of the Invention: TECHNICAL FIELD OF THE INVENTION The present invention relates to a copper alloy, and more particularly to a low-loss copper alloy. [Prior Art] The main component of brass is copper and rhodium. The ratio of the two is usually about 7:3 or 6.4, and usually contains a small amount of impurities. In order to improve the properties of brass, conventional brass contains lead (mostly 1-3 wt%) to achieve the desired mechanical properties of the industry, and thus has become an important industrial material, widely used in pipelines, faucets, water supply / drainage systems. Products such as metal devices or metal valves. However, with the rise of environmental awareness, the impact of heavy metals on human health and environmental pollution has gradually received attention. Therefore, limiting the use of lead-containing alloys is the current trend, and countries such as Japan and the United States have successively revised relevant regulations and pushed Reducing the error rate in the environment, including lead-containing alloy materials used in household appliances, automobiles, and water peripheral products, especially requiring that lead is not eluted from the product to drinking water' and lead pollution must be avoided during the processing. In addition, when the zinc content in the brass exceeds 20% by weight, the corrosion phenomenon of dezincification is easy to occur. 'Dezincification can seriously damage the structure of the brass alloy, and the surface strength of the brass product is lowered, or even yellow. The perforation of the copper tube greatly shortens the service life of the brass product and causes problems in application. In response to the above-mentioned problems of high lead content and off-line, the industry continues to develop copper alloy formulations. In addition to the essential components of steel and zinc, such as US6413330, US7354489, US20070062615, US20060078458, US2004023441, the lead-free copper 201107500 alloy formulation is disclosed, and the above alloys have poor machinability. It has low processing efficiency and is not suitable for large batches of defects such as mass production, cracks and slag inclusion. In addition, for example, US Pat. No. 7,297,215, US Pat. No. 6,974,509, US Pat. The range of wt% to 7 wt%, however, the high bismuth content is liable to cause defects such as cracks and slag inclusions, resulting in low processing efficiency. In addition, in addition to the necessary components of copper and zinc, the anti-dezincification formula has been disclosed in US Pat. No. 4,417,929, which contains iron, Ming and Shi Xi; and § §55〇7885 and US6395110 disclose phosphorus, tin and nickel. Ingredients; US 5,653,827 discloses compositions comprising iron, nickel and ruthenium; U6974509 discloses components comprising tin, antimony, iron, nickel and phosphorus; US 6,787,101 discloses both phosphorus, tin, nickel, iron, aluminum, antimony and arsenic; and US65993? And the removal of 6316 () and other special (10) and phosphorus and other ingredients added to the brass alloy to achieve anti-zinc removal effect. However, copper is often high in sputum (more pains), which is beneficial to the coldness of brass materials, but it is high in the amount of fresh produce and (4) lead pollution in the process. Although the industry wants to develop new brass materials, look for gold and copper, and achieve resistance to dezincification, it is still necessary to combine alloy properties such as conversion properties, machinability, corrosion resistance, and mechanical properties. SUMMARY OF THE INVENTION In order to achieve the above and the purpose of Wei, the present invention provides a key copper alloy, ^. Γ5 to G.3 heavy autumn (four)) b); G·3% by weight (Α0 ' 〇. 0% by weight of coffee; % by weight of coffee, · and 201107500, more than 96.5 wt% of copper (Cu) and zinc (Zn), wherein the content of copper in the low-error copper alloy is 58 to 70% by weight. The low-distortion copper alloy of the present invention is a brass alloy, and the total content of copper and zinc is up to 96.5 wt% or more. In the embodiment, the content of the steel is the weight of the curse to the '% of the range of copper can provide an alloy Good _ sex, which facilitates subsequent processing of the alloy material. In a preferred embodiment, the steel content is from 62 to 65 parts by weight of the copper alloy of the present invention, and the content of the aluminum is from 〇3 to 〇8% by weight. In a preferred embodiment, the content of the present invention is from 0.4 to 7% by weight, more preferably from 5% to 0.65% by weight. The addition of an appropriate amount of aluminum increases the fluidity of the copper water and improves the prayer performance of the alloy material. In the copper alloy of the present invention, the content of the cerium is 〇4% by weight or less. In the preferred embodiment, the cerium content is 0.01 to 0.4% by weight, preferably 〇〇5 to 〇·3% by weight, more preferably 0.1 to 0.2% by weight. In the copper alloy of the present invention, the content of the nickel is from 0.1 to 2% by weight. In the example, the weight of nickel is 0.5 to 1% by weight. Adding an appropriate amount to the copper alloy can be used as a high melting point element, and nickel is used as a heterogeneous core which does not spontaneously form a core when the alloy is crystallized, so that the number of nucleation sites increases. The alloy crystal grains can be refined; and the nickel can purify the copper matrix and the grain boundary, and the mechanical properties and corrosion resistance of the copper alloy can be improved. The copper alloy of the invention has an extremely low lead content of 0.3% by weight or less. In the embodiment, the lead content is 〇.〇5 to 3.3% by weight, preferably 〇1 to 〇25% by weight, more preferably 0.15 to 0.20% by weight. The alloy may also have impurities. The inevitable impurity content is 〇1% by weight or less. The copper alloy of the present invention can replace the conventional lead-containing brass, and can more effectively achieve environmental protection and 201107500. The effect of reducing lead pollution is also resistant to dezincification corrosion, and At the same time, taking into account the casting properties, machinability, corrosion resistance, and [Embodiment] The embodiments of the present invention are described by way of specific embodiments, and those skilled in the art can understand the other advantages and advantages of the present invention. Unless otherwise stated, the components contained in the dezincification-resistant copper alloy are based on the total weight of the alloy and expressed in weight percent (wt%) _. When the content is high (1 wt% or more) When added to a brass alloy, microscopically, it is easy to form a liquid film in the grain of the brass alloy, and finally segregate at the grain boundary to produce a continuous sheet-like flaw, which blocks the grain boundary and causes the mechanical strength of the alloy to collapse. The hot brittleness and cold brittleness of the alloy increase, causing cracking of the material. However, according to the low-angle brass alloy formulation of the present invention, it is only necessary to use the crucible below 〇4, which not only solves the defects of material cracking but also can reach the material of lead brass (such as the conventional H59 fault brass). Characteristics (such as machinability, etc.), and are not susceptible to product defects such as cracks or inclusions. Therefore, the low-error brass alloy of the present invention can greatly reduce the amount of niobium and effectively reduce the production cost of the low-lead brass alloy, and is extremely advantageous for commercial mass production and application. In addition, the low-loss brass alloy formulation according to the present invention can reduce the lead content of the alloy to 0.05-0.3 wt%' in accordance with international regulations for lead content in pipeline materials in contact with water. Therefore, the low-lead brass alloy according to the present invention is advantageous for the manufacture of faucets and bathroom components, water pipes, water supply systems, etc. 201107500. In one embodiment, the low-lead brass alloy of the present invention includes: 0 〇5 to 〇 3 wt% of lead; 0. 3 to 0.8 wt% of aluminum; 0.01 to 04 wt% of secret; 〇a to 2 wt% of nickel; and 96.5 to 99.54 wt% of copper and rhodium, wherein the copper is The content of the low-error brass alloy f is 58 to 70% by weight. In another embodiment, the nickel-containing low-lead brass alloy of the present invention comprises: 0.1 to 0.25 wt% lead; 0.4 to 0.7 wt%; 〇.〇5 to 3.3 wt% Μ; 0.5 To 1% by weight of nickel; 58 to 70% by weight of copper; and the balance of zinc; and the unavoidable impurity content is 0.1% by weight or less. In still another embodiment, the nickel-containing low-lead brass alloy of the present invention comprises: 0.15 to 0.20% by weight of lead; 5.5 to 0.65% by weight of aluminum; 0.1 to 0.2% by weight of bismuth; 0.5 to 1 by weight. % nickel; 62 to 65% by weight of copper; and the balance zinc; and the unavoidable impurity content is 0.1% by weight or less. Hereinafter, the present invention will be described in detail by way of illustrative embodiments. The components of the low-lead copper alloy of the present invention used in the test examples described later are as follows: wherein the ratio of each component is based on the total weight of the alloy: Example 1: A1: 0.457 wt% Ni: 0.584 wt% Zn: margin

Cu : 61.54 wt%

Bi : 0.197 wt%

Pb ' 0.144 wt% 201107500 Example 2 : Cu : 62.72 wt % A1 : 0.634 wt % Bi : 0.126 wt % Ni : 0.853 wt % Pb : 0.178 wt % Zn : balance Example 3 : Cu : 62.45 wt % A1 : 0.582 wt% Bi : 0.159 wt% Ni : 0.696 wt% Pb : 0.156 wt% Zn : balance test example 1: sand core was prepared by a core shooting machine using round sand, urea resin, furan resin and curing agent as raw materials, and The amount of gas generated by the resin was measured by a gas tester. The resulting sand core must be used within 5 hours, otherwise it should be dried in an oven. The low-lead brass alloy and the reclaimed material of the present invention are preheated for 15 minutes to bring the temperature to 400 ° C or higher, and then both are smelted in an induction furnace at a weight ratio of 7-1 and added 0.2 wt%. Refining the slag agent, until the brass alloy reaches a certain molten state (hereinafter referred to as melting copper liquid), casting with a metal gravity casting machine with a sand core and a recasting mold, and controlling by a temperature monitoring system to maintain the casting temperature Between 1010-106 (TC. The casting amount is 1-2 kg for each casting, and the casting time is controlled within 3-8 seconds. After the mold is cooled and solidified, the mold is opened and unloaded to clean the pouring riser, and the mold temperature is monitored. 201107500 f 'The mold temperature is controlled in the winning and forming the casting, and then the prayer is removed. After each mold casting is taken out, the mold is cleaned to ensure that the core is touched clean, and the graphite is sprayed on the surface of the mold and then immersed in water for cooling. The temperature of the graphite water for cooling the mold is 30_36 <) C, and the specific gravity is 1.05 to 1. 〇6. “The cooled castings are self-tested and sent to the sand cleaning machine for pottery sand cleaning. Then, 'the blank processing (heat treatment of the casting scale (clearing stress annealing) is performed to eliminate the internal stress generated by the casting). Machining and polishing, so that the inner cavity of the casting has sand, metal county (4). Conduct quality inspection analysis and calculate the total production yield: total production yield = number of good products / total number of products X 100% total production yield of the process It reflects the quality stability of the production process, and the higher the quality stability, can ensure the normal production. Another high-nickel lead-free brass and the conventional H59 lead brass are used as comparative examples to prepare the objects in the same process as the above. The composition, processing characteristics and total production yield are as shown in Table 1. The brass material in which the 'error content is less than 0.05 wt% is regarded as error-free brass. 201107500

Table 1. Item high nickel lead-free brass H59 lead brass Low lead brass alloy of the present invention Comparative Example 1 Comparative Example 2 Comparative Example 4 Comparative Example 1 Example 2 Example 3 Cu content measured (%) 61.01 62.74 59.7 61.1 61.54 62.72 62.45 A1 content measured (%) 0.574 0.621 0.521 0.589 0.457 0.634 0.582 Pb content measured (%) 0.0067 0.0115 2.16 1.54 0.144 0.178 0.156 Bi content measured (%) 0.134 0.118 0.0074 0.0089 0.197 0.126 0.159 Ni content measured 2.324 2.101 0.0103 0.0057 0.584 0.853 0.696 Foundry yield 91% 90% 93% 95% 92% 91% — — 91% Machine plus yield 80% 82% 98% 99% 98% 98% 97% Polishing yield 94% 95% 95% 94% 96% 97% *--- 97% Total yield 68.4% 70.1% 86.6% 88.4% 86.6% 86.5% 85.6% The high nickel lead-free brass has a higher hardness and therefore is intended for high nickel lead-free yellow steel. Machining is more difficult. When the above three kinds of brass materials have the same feed amount and the same cutting speed, the surface of the high-recording and error-free brass product is likely to leave a knife mark, and the surface roughness is not required (ie, the Ra value is 3.2. Μιη), because of the low yield of production. 201107500 According to the test group of the low lead brass according to the present invention, the production yield = up to 85% or more, which is equivalent to the conventional lead copper, which can be used as a substitute for steel materials. The low-lead brass of the present invention can greatly reduce the lead contained in the alloy. 'Effectively avoiding the fouling generated in the process, and reducing the amount of mis-discharge when using the transferred article, and at the same time taking into consideration the material properties. Meet environmental requirements. Test Example 2:

A test piece of the low lead copper alloy (Example 丨), high nickel lead-free brass (Comparative Example 1), H59 lead brass (Comparative Example 3), and low nickel lead-free brass (Comparative Example 5) of the present invention was optically observed. The tissue distribution of the material under the metallographic microscope was magnified 100 times as shown in Fig. 1A-1C. The composition of the nickel-containing low-lead brass of Example 1 was found to be Cu: 6154% % 'A1: 0.457 wt% 'Pb: 0.144 wt% > Bi: 0.197 wt% > Ni: 0.584 wt%. The metallographic structure distribution, as shown in Fig. A, will form fine crystal grains with a grain size of about 15-25 μm, which provides better material toughness and is less prone to cracks and other defects. Compared with the comparative example, the crystal grains of the iia phase of the example were finer and denser, indicating that the material had good mechanical properties. The high nickel lead-free brass composition of Comparative Example 1 was found to have Cu: 61 〇ι maple %, A1: 0.574 wt %, Pb: 0.0067 wt %, Bi: 0.134 wt %, and Ni: 2 324 wt %. The metallographic structure distribution is as shown in Figure IB, and the crystal grains are fine-grained, so that the material has a higher hardness. The measured value of the main component of H59 lead brass of Comparative Example 3 was: Cu: 59.7 wt% 'Al: 0.521 wt% 'Pb: 2.16 wt% > Bi: 0.0074 wt% 'Ni: 0.0103 wt%. Its metallographic structure is shown in the figure ic, which is an α-phase alloy. The crystal 11 201107500 has a round granular shape with a particle size of about 30_40μηι and good toughness. In addition, the low nickel content: §: the error-free yellow steel is used as the comparative example 5, and the measured values of the main components are: Cu: 63.28 wt%, Al: 0.597 wt%, Pb: 0.037^%,

Bi. 114 wt%, Ni · 0.063 wt%, wherein the content of the brocade of Comparative Example 5 was less than 0.1%. The metallographic structure distribution is as shown in Fig. 1D. The crystal grains are narrow and coarse, and the size of the crystal grains is about 40-50 μm, indicating that the low-nickel lead-free brass has no effect of refining crystal grains. Test Example 3: Dezincification tests were carried out using the brass alloys of Example 3 and Comparative Example 3 to examine the corrosion resistance of brass. The dezincification test was carried out in accordance with Australia's eight 82345-2006 "copper alloy anti-dezincification" standard. Before the corrosion test, the phenolic wax was used to mount it and the exposed area was 100 mm2. All the test pieces were ground and smoothed with 600# metallographic sandpaper, and washed and dried with distilled water. The test solution was a ready-to-use l% iCuCl2 solution at a test temperature of 75 ± 2C. The test piece and the CuCl2 solution were placed in a constant temperature water bath for 24 ± 0.5 hours 'after cutting and then cut longitudinally'. After polishing the cross section of the test piece, the corrosion depth was measured and observed by a digital metallographic electron microscope. The result is shown in Fig. 2AA2b. Shown. The average dezincification depth of the low-error brass of the present invention of Example 3 was 141 72 μηη as shown in Fig. 2A. The average dezincification depth of the H59 yellow steel of Comparative Example 3 was 307.94 μπι ‘ as shown in Fig. 2 . The above results confirmed that the low-error yellow copper of the present invention has better resistance to dezincification. Test Example 4: This example was tested for mechanical properties in accordance with the IS06998-1998 "Metal Material Room Temperature Tensile Test" standard, and the results are shown in Table 2 below. 12 201107500 Table 2. • Slant Mechanical Properties Type Tensile Strength (Mpa) Elongation (%) Hardness (HRB) 1 2 3 4 5 Average 1 2 3 4 5 Average 1 2 3 4 5 Average Example 1 377 395 401 385 378 387.2 14 13 12 11 12 12.4 52 56 69 64 67 61.6 Comparative example 1 392 413 394 388 405 398.4 12 12 13 14 11 12.4 57 68 72 77 69 68.6 Comparative example 3 356 337 363 374 367 359.6 12 11 13 13 12 12.2 54 53 62 49 64 56.4 It can be seen from Table 2 that the tensile strength and elongation of Example 1 are comparable to those of the conventional H59 lead brass of Comparative Example 3, indicating that the low lead brass alloy of the present invention has the equivalent of H59 lead brass. The mechanical properties; however, the low-lead brass of the present invention has a low lead content and meets environmental protection requirements, and can indeed be used to manufacture products by replacing H59 wrong brass. • Although the high-nickel lead-free brass of Comparative Example 1 has higher strength and hardness, the high hardness is not conducive to the difficulty of alloy cutting processing, and the cost is also increased, which is not suitable for mass production of sanitary products. Test Example 5: According to the NSF 61-% SPAC single product metal allowable precipitation standard test, the metal of the brass alloy in the ring that is in contact with water ϊ ’ results are shown in Table 3 below:

13 201107500

table 3

The material of Comparative Example 3 has a large value of error when it is not washed, and only the solid 1 is not subject to the private treatment, that is, it is in accordance with the heavy metal of the alloy (4) (four), which is lower than the copper of the H59 ship. More in line with Wei' and have a view of human health.

In view of the above-mentioned 'Benjia's brass alloy with Yanghua's grain structure, good alloy strength and _, it is not easy to produce or pinch defects, and will not produce casting defects, up to Wenghuang _ (4) material miscellaneous, 俾Conducive to the alloy material is suitable for subsequent processes. The low-alloy of the present invention has the effect of low scale without the need for washing treatment, which can reduce the production cost of the process, and has great advantages for commercial mass production and application. The above examples are merely illustrative of the low lead copper alloys of the present invention and are not intended to limit the invention. Modifications and variations of the above-described embodiments may be made by those skilled in the art without departing from the spirit and scope of the invention. Accordingly, the scope of the invention is set forth in the appended claims. [Simple diagram of the diagram] 201107500 Figure 1A is a metallographic structure of the low-loss copper alloy test piece of the present invention; Figure 1 is a metallographic structure of the high-nickel error-free brass test piece; Figure 1C shows the lead of the Η59 lead The metallographic structure of the brass test piece; Figure 1D is the metallographic structure of the low-nickel lead-free brass test piece; 苐2Α is the metallographic phase of the low-loss copper alloy test piece for dezincification resistance test The tissue distribution map; and the second figure. The figure shows the metallographic structure of the anti-dezincification test of the Η59 wrong brass test piece. [Main component symbol description] Μ.

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Claims (1)

201107500 ·* VII. Patent application scope: - 1. A low-error copper alloy, including: 0.05 to 0.3% by weight of lead; 0.3 to 0.8% by weight of aluminum; 0.01 to 0.4% by weight of bismuth; 0.1 to 2% by weight of nickel And more than 96.5% by weight of copper and zinc, wherein the copper is contained in the low-lead copper alloy in an amount of 58 to 70% by weight. 2. The low-error copper alloy according to claim 1, wherein the copper content is from 62 to 65% by weight. • 3. For the low-lead copper alloy in the first application of the patent scope, the lead content is 0.15 to 0.25 wt%. 4. A low-lead copper alloy as claimed in claim 1 wherein the aluminum content is from 0.5 to 0.65% by weight. 5. The low-lead copper alloy according to item 1 of the patent application, wherein the content of the niobium is 0.1 to 0.2% by weight. 6. The low-error copper alloy according to claim 1, wherein the nickel content is from 0.5 to 1% by weight. 16