电镀层质量对可伐合金应力腐蚀断裂的影响

The Effect of the Electroless Plating Quality on the Stress—corrosion Fracture of Kovar Alloy

可伐合金用来制作半导体管及固定电路的外引线时常采用镀层进行防腐保护。但是这种外引线易发生应力腐蚀断裂。在镀层有缺陷时,镀金、镀镍层均促进可伐合金的应力腐蚀开裂。其断裂机理为氢致开裂。减少镀层缺陷可大大减少可伐合金外引线的应力腐蚀断裂。

The Kovar alloy used for the outlet of fixed circuit is often plated to preseve from cor rosion.But the outlet of fixed circuit made of the alloy is easy for delay fracture to occur.When defect exists in the plating the gold—plating,nickel—plating both promote the stress—corrosion fracture of the Kovar alloy.The reason of fracture is hydrogen britlenss,the reduction of plating defect will great ly reduce the stress—corrosion fracture of the outlet.