ZINC ALLOY AND MANUFACTURING METHOD THEREOF

Abstract

The present application relates to a zinc alloy and a manufacturing method thereof. The zinc alloy of the present application contains Al at an amount of 3.5-4.3 wt % and Mg at an amount of 0.005-0.018 wt %, and the rest of the alloy is Zn and unavoidable impurities. The alloy has excellent crack resistance, high casting yield, excellent polishing and electroplating properties, and can meet the high surface quality requirements of castings. It is suitable for die-casting production of components of plumbing and sanitary ware, hardware accessories, electronic appliances, toys and the like.

Claims

1. A zinc alloy, wherein the zinc alloy contains Al at an amount of 3.5-4.3 wt % and Mg at an amount of 0.005-0.018 wt %, and a remainder of the alloy is Zn and unavoidable impurities.

2. The zinc alloy according to claim 1, wherein the amount of Al in the zinc alloy is 3.7 to 4.2 wt %.

3. The zinc alloy according to claim 1, wherein the amount of Al in the zinc alloy is 3.9-4.1 wt %.

4. The zinc alloy according to claim 1, wherein the amount of Mg in the zinc alloy is 0.005-0.015 wt %.

5. The zinc alloy according to claim 2, wherein the amount of Mg in the zinc alloy is 0.005-0.015 wt %.

6. The zinc alloy according to claim 3, wherein the amount of Mg in the zinc alloy is 0.005-0.015 wt %.

7. The zinc alloy according to claim 1, wherein Cu with an amount of 0.2-1.0 wt % can be selectively added to the zinc alloy.

8. The zinc alloy according to claim 2, wherein Cu with an amount of 0.2-1.0 wt % can be selectively added to the zinc alloy.

9. The zinc alloy according to claim 3, wherein Cu with an amount of 0.2-1.0 wt % can be selectively added to the zinc alloy.

10. The zinc alloy according to claim 4, wherein Cu with an amount of 0.2-1.0 wt % can be selectively added to the zinc alloy.

11. The zinc alloy according to claim 1, wherein the amount of Cu in the zinc alloy is 0.5-1.0 wt %.

12. The zinc alloy according to claim 2, wherein the amount of Cu in the zinc alloy is 0.5-1.0 wt %.

13. The zinc alloy according to claim 3, wherein the amount of Cu in the zinc alloy is 0.5-1.0 wt %.

14. The zinc alloy according to claim 4, wherein the amount of Cu in the zinc alloy is 0.5-1.0 wt %.

15. The zinc alloy according to claim 5, wherein the amount of Cu in the zinc alloy is 0.5-1.0 wt %.

16. The zinc alloy according to claim 1, wherein the alloy does not contain Zr, Sb, Cr, Mn, Ti, Bi, Se, Ni and the like, except that these elements are present as impurities in the zinc alloy each with an amount of less than 0.001 wt %.

17-19. (canceled)

Description

DETAILED DESCRIPTION OF EMBODIMENTS

[0023] The present application will be further described in detail below in conjunction with specific embodiments and drawings.

[0024] The compositions of the alloys of the present application and the comparative alloys are shown in Table 1.

[0025] The alloy of the present application and the comparative alloy are prepared according to the following steps: weighing zinc ingots, aluminum ingots, magnesium ingots and selectively electrolytic copper according to the composition of the zinc alloy; adding the aluminum ingots, and selectively electrolytic copper, and ⅓ of the zinc ingots at the bottom of a furnace, stirring evenly after all materials are melted, adding the remaining zinc ingots, and using a bell to press the magnesium ingot to the bottom of the furnace at about 540° C. after the materials are all melted, after the magnesium ingot is melted, selectively adding a refiner; which may be titanium salt, adding a purifying agent for purifying after the refiner is fully reacted, then removing residue and gas, allowing a product to stand after a composition test is qualified and casting after slagging and taking out of the furnace.

[0026] The alloy of the present application is a boat-shaped ingot for remelting.

[0027] Performance testing of the alloy of the present application and the comparative alloy is carried out. The specific performance testing items and basis are as follows:

[0028] 1. Casting Performance

[0029] The flow length of the melt is measured using a spiral specimen commonly used in casting alloys, and the fluidity of the alloy is evaluated, which is used to evaluate the casting performance of alloys 1-8 of the present application and comparative alloys 1-6. All samples are cast by hand, and the casting temperature is 420° C.±2° C. The results are shown in Table 2.

[0030] 2. Resistance to Hot Crack of the Product

[0031] The same mold, the same die-casting machine, the same die-casting parameters, the same operator are used to die cast the alloy 1-8 of the present application and the comparative alloy 1-6 to form the same product, with a die-casting temperature of 420° C.±10° C. The defective rates regarding die-casting cracks are shown in Table 2.

[0032] 3. Polishing Performance

[0033] The castings are polished separately, and then observed with naked eyes. If there are no hard spots, the result is excellent and indicated by “◯”; if the total number of hard spots is more than 3, and the diameter of each hard spot is less than 0.5 mm (0.01969 inch), the result is bad and indicated by “X.” The results are shown in Table 2.

TABLE-US-00001 TABLE 1 The composition of the alloys of the present application and the comparative alloys (wt %) Other Example Al Mg Cu elements Refiner Zn Alloys of 1 3.50 0.005 added the remainder the present 2 3.70 0.01 the remainder application 3 3.90 0.007 the remainder 4 4.30 0.01 the remainder 5 4.1 0.015 0.2 the remainder 6 3.90 0.008 0.5 the remainder 7 4.05 0.01 0.7 the remainder 8 3.98 0.01 1.0 added the remainder Comparative ZAMAK 3 4.05 0.03 not added the remainder alloy 1 Comparative ZAMAK 5 3.98 0.05 0.7 not added the remainder alloy 2 Comparative 4.08 0.04 Zr: 0.04 not added the remainder alloy 3 Comparative 4.12 0.05 0.8 Ti: 0.03 not added the remainder alloy 4 Comparative 3.95 0.06 Mn: 0.5 not added the remainder alloy 5 Bi: 0.2 Comparative 4.20 0.03 Sb: 0.03 not added the remainder alloy 6

TABLE-US-00002 TABLE 2 Performances of the alloys of the present application and comparative alloys Casting Resistance to performance hot crack/hot flow Polishing crack defec- Example length/mm performance tive rate Alloys of 1 240 ∘ 5% the present 2 255 ∘ 8% application 3 262 ∘ 2% 4 280 ∘ 5% 5 257 ∘ 3% 6 268 ∘ 2.5%.sup.  7 259 ∘ 3% 8 276 ∘ 1% Comparative 1 (ZAMAK3) 251 ∘ 100%  alloys 2 (ZAMAK5) 243 ∘ 90%  3 238 x 85%  4 240 x 80%  5 228 ∘ 90%  6 234 ∘ 75% 

[0034] According to the performance test results in Table 2, it can be seen that as a casting alloy, the alloy of the present application has fluidity equivalent to that of ZAMAK3 and ZAMAK5 zinc alloys, but its resistance to hot cracking is significantly better than that of ZAMAK3 and ZAMAK5. The polishing performance of alloys 1-8 of the present application is better than that of comparative alloys 3 and 4. Among them, alloys 3, 5, 6, 7, and 8 of the present application have the best comprehensive properties such as crack resistance and polishing performance relatively. Alloys 3 and 8 of the present application which have an added refiner have better crack resistance. The crack resistance of comparative alloys 1-6 is not as good as that of the alloy of the present application. The crack resistance of comparative alloys 3-4 is relatively good, but the polishing performance thereof is poor, and thus they are not suitable for application to exterior parts of a bathroom with high polishing requirements.

[0035] In summary, the alloy of the present application has good casting properties, excellent crack resistance, excellent polishing, and electroplating properties, and is suitable for die-casting and gravity casting to produce components of plumbing, sanitary ware, hardware accessories, electronic appliances, toys, and the like, especially suitable for casting products prone to forming cracks.

[0036] The above-mentioned embodiments are used to explain the present application, not to limit the present application. Any modification and change made to the present application within the spirit of the present application and the protection scope of the claims shall fall into the protection scope of the present application.