Effects of different solution processes on microstructure and properties of the aged Cu-Cr-Sn-Zn alloy used in lead frame

The effects of different solution processes on microstructure and properties of the aged Cu-Cr-Sn-Zn alloy were researched. The results show that the grain size of rapid solidification sample is much smaller than that of the solution treatment one, also there are much finer precipitates in the rapidly solidified aged sample than in the solution aged one, so the strength of this alloy is enhanced obviously under rapid solidification aging than solution aging. Under the condition of solution treatment at 920°C for 1 h and aging at 500°C for 15 min, the hardness and electrical conductivity of this alloy can reach 102 HV and 50% IACS respectively, however they can reach 179 HV and 60% IACS respectively under rapid solidification and the same aging condition.