Simulation Analysis of Minimum Bending Radius for Lead Frame Copper Alloys

Article history: Received 2.11.2012 Received in revised form 10.12.2012 Accepted 10.12.2012 Copper alloy has a lot of excellent properties, so it becomes an important alloy for lead frame materials for the integrated circuit. The minimum bending radius of three different copper alloys (Cu-Fe-P, Cu-Ni-Si, Cu-Cr-Sn-Zn) for lead frame materials was analyzed by using finite element. Tensile tests for the three kinds of materials were done to obtain yield stress, ultimate strength and other parameters. The strain-hardening exponent n and normal anisotropy index r of the materials were obtained according to the tensile tests. The minimum bending radius of corresponding materials was available with the simulation analysis, and consequently, the bending properties of the different materials were compared. The results show that the bending property of Cu-CrSn-Zn alloy is the best, and Cu-Ni-Si alloy the worst.