Microstructure and mechanical properties of a CuNiTi alloy with a large product of strength and elongation

Abstract

A Cu-10 Ni-2Ti wt.% alloy has been fabricated by induction melting and casting. The microstructure evolutions of the studied alloy treated with thermal-mechanical treatment were characterized. After homogenized at 950 °C for four hours, hot rolling by 80% at 900 °C solid solution treated at 970 °C for four hours, cold-rolled by 50%, aged at 450 °C for one hour, the hardness, electrical conductivity, tensile strength, yield strength, and the elongation of the studied alloy approached 181 HV, 22.1% IACS, 576 MPa, 486 MPa, and 14.6%, respectively. The studied alloy shows large products of strength and elongation (15.4 GPa·%, 9.3 GPa·%, 8.41 GPa·%, and 10.1 GPa·% for the samples treated with a solid solution, under aged, peak aged, and over-aged states), which are much higher than those of other high strength conductive copper alloys. These findings are helpful in designing new high damage tolerance conductive materials. Keywords: Cu alloy, Damage tolerance, Precipitation, Strength, Microstructure