钎缝厚度对陶瓷连接接头强度的影响

采用不同厚度的Ag-Cu-Ti钎料连接Si3N4陶瓷材料,研究了钎缝厚度对连接强度的影响规律,利用扫描电镜观察了接头微观结构.试验发现,在一定钎缝厚度范围内,随着钎缝厚度的增加,接头强度随之提高.研究表明:钎缝厚度影响连接强度的主要原因在于对残余应力的缓解,但钎缝厚度过厚时,对应力的缓解作用变化不大,而钎缝的拘束作用减弱,接头强度有下降的趋势;在相同连接规范下,钎缝厚度与反应层厚度之间也存在一定的关系.

Effects of weld thickness on the strength of Si3N4 joints

In this paper, Si_3N_4 ceramics were brazed with different thickness Ag-Cu-Ti alloy, and effects of weld thickness on the joint strength were investigated. Microstructures of joints were observed by SEM. Results indicated that, within certain range, the joint strength increased with the increase in weld thickness. It was concluded that the thickening of weld relaxed some residual stresses, thereby reinforcing the joint. When the weld thickness is too thick, the increase of thickness has little effect on relaxing stress, while the restraint effect of weld decrease, it makes the strength of joint decrease.In addition, microstructures showed that, under same bonding parameters, weld thickness related in some way to the thickness of reaction layer.