The Cu-Ni-Cr alloy strip was produced by medium frequency furnace smelting and iron mould casting

and then hot rolling

then solid solution and aging treatment.Effects of different heat treatment specifications on microstructure and properties of the alloy have been examined by tensile testing

electric conductivity measurements

optical microscope and transition electron microscope observation.The results reveal that the pre-cold deformation and sub-structure strengthening resulting from aging as well as the precipitating strengthening of Cr particles precipitated from supersaturated solid solution are responsible for the high strength of the alloy.The pre-cold deformation of alloy before aging can greatly improve the strength with the little decrease of electric conductivity.The tensile strength

yield strength

elongation and electric conductivity of alloy are 415.2 MPa

368 MPa

13.2% and 23.89 MS/m

respectively

with 50% cold deformation and then holding for 4 hours at 450 ℃.