Evolution of microstructure and properties of Cu-4.5 wt.% Ag alloy prepared by vacuum horizontal continuous casting in solid solution and aging treatment

Abstract

The vacuum horizontal continuous casting method was used for preparing Cu-4.5 wt.% Ag alloy rod containing few oxygen. The evolution of microstructure was observed by metallographic microscope (OM), scanning electron microscope (SEM) and transmission electron microscope (TEM). The results showed that the hardness and electrical conductivity of Cu-4.5 wt.% Ag alloy aged at 450 °C for 12 h were increased by 60 HV and 12 %IACS than solution treated alloy. TEM observation showed that the continuous precipitates of Ag are uniformly distributed in matrix with the form of particles and strips. Through calculation, the strength increment of peak aged Cu-4.5 wt.%Ag alloy from solid solution hardening and precipitation hardening are 86 MPa and 136 MPa, respectively.

Keywords

• Cu-Ag alloy
• casting method
• oxygen content
• strengthening mechanism