Effects of temperature and strain rate on tensile properties of Cu-Cr-Zr-Ti Alloy

Abstract

Effects of temperature and strain rate on the tensile properties of Cu-Cr-Zr-Ti alloy in annealed condition were investigated by varying the initial strain rates from 10−4s−1 to 10−1s−1 at RT, 300°C, 450°C, 600°C and 700°C. The yield strength (YS) and ultimate tensile strength (UTS) of the alloy increased with an increase in strain rate at RT and 300°C, whereas at 450°C, the material exhibited the highest YS and UTS at the lowest strain rate of 10−4s−1. At 600°C, the YS and UTS of the alloy increased with an increase in strain rate and showed the highest YS compared to all the temperatures tested. The alloy showed serrated yielding at 300°C and at an initial strain rate of 10−4s−1 whereas at 450°C, serrated yielding was observed at 10−3s−1 and 10−4s−1 strain rates. Microstructural observations showed the presence of creep cavities at 450°C and strain rate of 10−4s−1. The creep cavities were present at higher strain rates as the test temperature is increased. Fractography indicates that the fracture is predominantly dimple fracture at RT and 300°C and intergranular cracks were observed at 600°C and 700°C.