Button or fastener member of copper-plated aluminum or aluminum alloy and method of production thereof
A button or fastener member is provided wherein aluminum or an aluminum alloy is used as raw material, a first copper plating layer is formed directly over the entire surface of said raw material, and a second copper plating layer is formed directly on top of the first copper plating layer, with the aforementioned second copper plating layer being thicker than the aforementioned first copper plating layer.
1. A button or fastener member, comprising:
a button or fastener member formed of aluminum or an aluminum alloy;
a first copper plating layer directly covering an entire surface of the button or fastener member formed of aluminum or an aluminum alloy; and
a second copper plating layer directly covering the first copper plating layer, wherein the second copper plating layer is thicker than the first copper plating layer,
wherein a mean crystal grain size of the first copper plating layer is 0.7 μm-1.1 μm and a mean crystal grain size of the second copper plating layer is 0.2 μm-0.6 μm.
2. The button or fastener member of claim 1 , wherein a mean thickness of the first copper plating layer is 0.01-1.5μm, and a mean thickness of the second copper plating layer is 1.6-10 μm.
3. The button or fastener member of claim 1 , wherein a final plating layer covers the second copper plating layer.
4. The button or fastener member of claim 3 , wherein an overall thickness of the final plating layer is thinner than a total thickness of the first copper plating layer and the second copper plating layer.
5. The button or fastener member of claim 1 , further comprising a final plating layer covering the second copper plating layer, wherein the final plating layer is a copper-tin alloy plating, a nickel-plating layer, or a combination thereof and wherein an overall thickness of the final plating layer is 20%-60% of a total thickness of the first copper plating layer and the second copper plating layer.
6. A method for producing a button or fastener member according to claim 1 , the method comprising:
forming a semi-finished member from aluminum or an aluminum alloy;
forming the first copper plating layer directly over surfaces of the semi-finished member by electric strike-plating copper onto the surfaces using barrel plating; and
forming the second copper plating layer directly over the first copper plating layer through electric-plating copper using a barrel.
7. The method of claim 6 , wherein a mean crystal grain size of the first copper plating layer is larger than a mean crystal grain size of the second copper plating layer.
8. The method of claim 6 , wherein forming a second copper plating layer starts within one minute after conclusion of the forming of the first copper plating layer.
9. The method of claim 6 , wherein the mean thickness of the first copper plating layer is 0.01-1.5μm, and the mean thickness of the second copper plating layer is 1.6-10μm.
10. The method of claim 6 , further comprising:
forming a final plating layer on top of the second copper plating layer.
11. The method of claim 6 , wherein an overall thickness of the final plating layer is thinner than a total thickness of the first copper plating layer and the second copper plating layer.
12. The method of claim 6 , further comprising:
pretreating the semi-finished member prior to forming a first copper plating layer on the semi-finished member by degreasing, acid washing, washing with a surfactant or water washing the semi-finished member.
13. The method of claim 12 , wherein pretreating the semi-finished member and forming a first copper plating layer are performed within a single barrel.