顶镦Ag-Cu复合触点Ag层厚度分布的研究

Thickness Distribution of the Ag Layer for the Upsetted Ag- Cu Composite Contact

目的解决继电器Ag-Cu复合触点顶镦成形后,Ag层厚度分布不均的问题。方法通过数值模拟分析了其预成形和终成形过程中等效应变的分布,以及Ag-Cu界面形状的变化规律及影响因素,并在预成形形状和摩擦因数方面,提出了改善Ag层厚度均匀性的措施。结果预成形模具形状及工件与模具间的摩擦,对成形结果的影响很大。结论半锥角α取值居中时,终成形后易获得均匀的Ag层厚度分布;减小Ag-上模间摩擦因数或增大Cu-下模间摩擦因数,则有利于增加终成形后Ag层厚度分布的均匀性。

Objective To solve the uneven thickness distribution of the Ag layer for the upsetted Ag- Cu composite relay contact. Methods Numerical simulation was used to analyze the distribution of effective strain during the process of preforming and final forming,and the change pattern of the shape of Ag- Cu interface and its influencing factors were also considered. And then,some measures to improve the thickness uniformity of the Ag layer were proposed from the aspects of preform shape and friction coefficients. Results The preform die shape and the friction between the workpiece and its dies had a great influence on the forming results. Conclusion It is easy to obtain uniform thickness distribution of the Ag layer after final forming,when an intermediate value is taken for the half cone angle α. It＇s beneficial to increase the uniformity of thickness distribution of the Ag layer,if the friction coefficient of Ag- upper die is increased or the friction coefficient of Cu- lower die is increased.