Micro-hardness and electric conductivities of Cu-0.43Cr-0.058Zr-0.031Y and Cu-0.20Cr-0.066Zr-0.060Y alloys treated by solid solution at 900～980 ℃ were measured

and microstructures of these solid solution alloys were observed.The results show that Cu-0.43Cr-0.058Zr-0.031Y alloy can be treated by solid solution at 960 ℃ while Cu-0.20Cr-0.066Zr- 0.060Y alloy only treated within 920 ℃.The comparison of electric conductivity and micro-hardness between the two solid solution treatment alloys after ageing at 400～520 ℃ reveals that the electric conductivity of Cu-0.43Cr-0.058Zr-0.031Y alloy is lower than that of Cu-0.20Cr-0.066Zr-0.060Y alloy after ageing at 400 ℃ while ageing at 480 ℃

Cr content can be ignored in effects on electric conductivity of two kinds of alloys.The hardness of Cu-0.43Cr-0.058Zr-0.031Y alloy is obviously lower than that of the Cu-0.20Cr-0.066Zr-0.060Y alloy regardless of ageing at 400 ℃ or 480 ℃.