Hard coated copper alloys, process for production thereof and connector terminals made therefrom

A coated Cu alloy comprising a Cu alloy having a surface coating formed directly on an outer surface of said Cu alloy, said surface coating having a thickness of 0.5 to 20 .mu.m, said surface coating containing an intermetallic compound consisting essentially of Cu and Sn, said surface coating having an Hv hardness of above 450 and a thickness of between 1 and 10 .mu.m;

• and said Cu alloy consisting essentially of 0.1-15 wt % Ni, 0.1-10 wt % Sn, 0.005-0.5 wt % P, and 0.01-40 wt % of a total of at least one auxiliary element selected from the group consisting of Fe, Co, Zn, Ti, Mg, Zr, Ca, Si, Mn, Cd, Al, Pb, Be, Te, In, Ag, B, Y, La, Cr, Ce and Au, with the remainder of the alloy being copper, wherein each of said at least one auxiliary element is in the following amount:
• ______________________________________ Zn:
• 0.01-40 wt %;
• Co:
• 0.01-5 wt %;
• Ti:
• 0.01-5 wt %;
• Fe:
• 0.01-5 wt %;
• Zr:
• 0.01-3 wt %;
• Ca:
• 0.01-1 wt %;
• Mg:
• 0.01-3 wt %;
• Mn:
• 0.01-10 wt %;
• Cd:
• 0.01-5 wt %;
• Si:
• 0.01-3 wt %;
• Pb:
• 0.01-5 wt %;
• Be:
• 0.01-3 wt %;
• Al:
• 0.01-10 wt %;
• In:
• 0.01-5 wt %;
• Ag:
• 0.01-5 wt %;
• Te:
• 0.01-5 wt %;
• Y:
• 0.01-5 wt % La:
• 0.01-5 wt %;
• B:
• 0.01-1 wt%;
• Ce:
• 0.01-5 wt %;
• Au:
• 0.01-5 wt %. Cr:
• 0.01-5 wt%;
• ______________________________________