板材厚度对铜合金冷轧薄板表面起皮的影响

Effect of Sheet Thickness on Surface Peeling in Cu-Fe-P Lead Frame Alloy

引线框架Cu-Fe-P合金薄板在精轧后表面产生起皮,经微观分析表明起皮破坏处有较大的Fe颗粒存在,且精轧前Fe颗粒周围已有裂纹。利用有限元数值分析法研究了不同板厚对Fe颗粒周围的应力分布的影响。结果表明,板厚较薄时,Fe颗粒和铜基体界面处存在明显的应力集中,应力集中将精轧前Fe颗粒周围的裂纹扩展,从而发生Cu-Fe-P表面起皮破坏。

Surface peeling occurred on the lead frame Cu-Fe-P alloy after finish rolling, By means of mierostructure analysis it was found that there were some larger Fe particles umder the damaged surface of sheet, and some microcracks existed around the Fe particles before finish rolling,The effect of sheet thickness on the stress around Fe particles in Cu-Fe-P allloy was invesigated using finite element digital analysis method,The results show that the stress concentration between the Fe particles and Cu matrix is the main factor to result in the microcracks and surface damage .The smaller the thickness of sheet, the larger the stress concentration at the interface between matrix and Fe particles, which will bring about the surface peeling of lead frame Cu-Fe-P alloy.