形状因子对微观定向结构Cu-W复合材料触头的力学和电学性能的影响

设计了三种微观定向结构的Cu-W复合电触头材料,用差异显著的形状因子对其表征,研究了形状因子对其导电性能和力学性能的影响。基于有效介质方程(GEM)和导电通道理论并结合仿真计算,得到不同骨架结构复合材料的电流密度分布及其与形状因子的关系。结果表明,形状因子F越接近1导电通道越容易形成团簇,导电性能越好；基于Mises屈服准则计算力学性能,仿真分析了不同结构复合材料的形变特性,提出其力学性能与形状因子的关系,即随着形状因子圆形度的增大力传导微元的稳定性随之提高；形状因子的圆形度越大,力传导微元越不易发生变形,机械性能越好。根据Cu-W复合电触头材料的导电性能和力学特性,可进一步优化其综合性能。

Influence of Shape Factor on Mechanical and Electrical Properties of Cu-W Composites with Micro-oriented Structure

Electrical contact Cu-W composites with three different micro-directional structure was designed, and characterized in terms of different shape factors. Then the influence of shape factors on their electrical conductivity and mechanical properties was investigated. Based on effective medium equation (GEM), conductive channel theory and simulation calculation, the current density distribution, and its relationship with the shape factor of composites with different skeleton structures were acquired. The results show that the closer the shape factor F to 1 is, the easier the formation of the cluster-like conductive channels are, thereby the better the conductivity is. The deformation characteristics of different composite materials were simulated and analyzed according to the Mises yield criterion, while the relationship between mechanical properties and shape factor was proposed, that is, with the increase of roundness of shape factor, the stability of force conduction element was improved. The larger the roundness of the shape factor is, the less deformation of the force conduction element is and the better the mechanical properties are. In a word, the comprehensive properties of the electrical contact Cu-W composite material can be further optimized by adjusting appropriately its conductivity and mechanical properties.