玻璃与金属真空钎焊接头残余应力影响参数分析

Analysis of influence parameters on residual stress in glass-to-metal vacuum brazing flat joint

玻璃和金属焊接接头由于设计不合理,将致使接头存在较大的焊接残余应力,会严重削弱接头强度.应用顺次耦合有限元热应力计算方法,对平板玻璃和金属在真空条件下的钎焊过程进行了数值模拟,分析了玻璃、金属、钎料厚度、钎焊压力和钎焊温度等因素对应力集中区域残余应力的影响,并观察了焊接接头拉伸断裂后的形貌特征.结果表明,金属厚度增加会增大残余应力,并且其对残余应力影响最显著;钎焊压力和钎焊温度的增加可以降低残余应力;玻璃和钎料厚度对残余应力的影响不大;焊接接头的拉伸断裂区域位于玻璃和金属焊接接头界面贴近玻璃一侧.

Because of unreasonable design,high residual stress exists in the glass-to-metal welding joint which results in the joint strength being weakened seriously.The finite element method of a sequentially coupling temperature field and welding residual field was used to simulate the vacuum brazing process of the glass and metal plate,the effects of the thickness of glass,metal and brazing filler metal,the brazing pressure and the brazing temperature on residual stress in the stress concentration area were analyzed,and the fracture morphological features of the welding joint were also observed through the tensile test.The results showed that the residual stress was increased with the increase of the thickness of metal,the thickness of metal had the greatest impact on the residual stress,the residual stress was reduced with the increase of brazing pressure and brazing temperature;the thickness of glass and brazing filler metal had little effect on the residual stress;the fracture area of the welding joint occured on the glass-to-metal interface which was close to the glass side.