Microstructure and properties evolution of high-strength conductive Cu-Ti-Fe-Cr alloy foils treated by combined aging process

Abstract:

Effects of combined aging process on microstructure and properties of age-hardenable Cu-3Ti-0.2Fe-0.2Cr alloy foils were investigated by mean of hardness test, tensile test, conductivity test, OM and SEM. It was shown that after the optimized combined aging treatment of pre-rolling with the reduction of 50%, pre-aging at 450 ℃ for 4 h, re-rolling with the reduction of 95.6% and re-aging at 450 ℃ for 1.5 h, the hardness, tensile strength, elongation and electrical conductivity of Cu-3Ti-0.2Fe-0.2Cr alloy foil were 354.6 HV, 1062 MPa, 1.9% and 17.1 %IACS, respectively. Compared with the specimen treated with Pre-0 h+CR+Re-2 h, the alloy foil treated with optimized combined aging process possessed the similar mechanical properties and higher electrical conductivity. The fractograph of the studied alloy foil treated with optimized combined aging process was composed of flat facets resembling cleavage, river pattern and dimples, manifesting a mixed-rupture mode.

Key words:Cu-Ti alloy; combined aging process; microstructure; electrical conductivity