复挤压对Ag-SnO2触点材料显微组织和性能的影响

Effect of multiple extrusion on microstructure and properties of Ag-SnO_2 contact materials

测试Ag-SnO2触点材料的加工性能和力学性能,借助扫描电镜(SEM)、能谱分析(EDS)和透射电镜(TEM)研究Ag-SnO2触点材料经过不同次数挤压后显微组织的变化,观察和分析材料中SnO2颗粒的分布及尺寸变化,得出Ag-SnO2触点材料性能与显微组织之间的关系。累积大塑性变形加工能够对Ag-SnO2触点材料的显微组织起到均匀化和弥散强化作用,从而使Ag-SnO2触点材料的抗拉强度随挤压次数的增加而降低,伸长率随挤压次数的增加而提高。

The working property and mechanical property of Ag-SnO2 contact materials were tested, the changes of their microstructure were studied by scanning electron microscopy, electron energy spectrum analysis, and transmission electron microscopy. The distribution and particle size change of SnO2 were also observed, the relation between the property and microstructure was noted, the influence mechanism of multiple extrusion on the properties and microstructure was explanted. After deformed by cumulative plastic deformation, SnO2 particles are homogenous and more dispersed in Ag-SnO2 composites. With increasing extrusion times, the tensile strength is reduced, while the elongation is increased.