不同微观组织对纯银整体铆钉触点静熔焊力的影响

Influence of Microstructure on Static Welding Force of Pure Silver Solid Rivet Contacts

对纯银整体铆钉采用退火处理,获得不同微观组织的触点。通过金相显微镜观察不同微观组织的触点,利用脉冲电流试验装置研究不同硬度触点压力-静熔焊力的变化规律,借助扫描电镜分析触点静熔焊后电弧侵蚀图像。结果表明,随着退火温度的升高,纯银整体铆钉触点晶粒长大,硬度下降;随着压力增加,不同硬度纯银整体铆钉触点的静熔焊力均出现递减趋势,压力超过9.9 N后递减趋势不明显;相同压力条件下硬度越大触点静熔焊力越大,电弧侵蚀越明显。

After annealing pure silver solid rivets,the contacts with different microstructures could be obtained,different microstructures of them were observed by metallographic microscope.The change rule of pressure-static welding force for the contacts with different hardness was investigated through pulse current device.Arc erosion images of contacts were analyzed by SEM.The result shows that grains of pure silver solid rivet contacts grow up but hardness decreases with the annealing temperature rising.As the pressure rises,static welding forces of pure silver solid river contacts have a trend to decrease,and this trend is not obvious when the pressure is larger than 9.9 N.At the same pressure,contacts with higher hardness have higher static welding force and more obvious arc erosion.