冲裁过程中镀层金属的流动规律

IT制件冲裁断面的氧化会降低接触面的导电性,并最终导致零件的功能失效.文中建立了平面应变刚塑性有限元分析模型,对冲裁过程中镀层金属的变形和流动情况进行了数值模拟;提出冲裁后断面镀层金属分布的估算方法,并以常用的锡镀层锡磷青铜带为例,进行了实验验证.研究结果表明:冲裁过程中,镀层金属主要流入到冲裁断面的圆角带和光亮带上;采用基于数值模拟的断面镀层金属含量估算方法获得的断面光亮带上镀层金属含量和试验结果一致.文中提出的方法可以用来在模具设计阶段评估不同冲裁工艺参数下冲裁断面的镀层金属含量,从而优选出断面镀层金属含量高的方案,达到提高断面抗氧化能力的目的.

Flow Law of Coating Metal in Blanking Process

The oxidation of blanking sections of IT products may weaken the contact conductibility and eventually lead to the function failure of products. In order to solve these problems, a plane-strain rigid-plastic finite element analysis (FEA) model is established to numerically simulate the deformation and flow of coating metal in the blanking process. Moreover, a method to estimate the distribution of coating metal in the blanking section is presented and is then verified by experiments using the tin-phosphorus-bronze band with Sn coating. The results show that the coating metal mainly disperses in the roll-over and the euphotic zones of blanking section during the blanking, and that the numerically-simulated content of coating metal in the euphotic zone of blanking section accords well with the experimental result. The proposed method can be applied to the die design for the purpose of estimating the content of coating metal on the blanking section at different blanking parameters, optimizing the parameters to increase the metal content and to further improve the antioxidant ability of the blanking section.