Effects of Vacuum Melting, Forging and Heat Treatment on Microstructure and Properites of Cu15Ni8Sn Alloy

The effects of vacuum melting and non-vacuum melting, forging, different aging temperature and re-solution-aging on the microstructure and mechanical properties of Cu15Ni8Sn alloy were studied. The results show that compared with non-vacuum melting ingot, the structure of vacuum melting ingot is more uniform, the strength is higher, but the elongation is lower. After hot forging of vacuum melting ingot, its structure is more uniform and its strengthening effect is obvious, but the elongation after 425 ℃ aging is lower, and the elongation after 375 ℃ aging is good. The mechanical properties of the sample with low elongation after 425 ℃ aging can not be improved when the secondary aging temperature is 425 ℃. When the aging temperature is 375 ℃, the strength is lower than that of 425 ℃ but the elongation is better. With the increase of aging time, the strength is higher, the aging strengthening effect of decreasing elongation is more obvious.