A comparison of brazed residual stress in plate–fin structure made of different stainless steel

In this study, design optimization of brazed residual stress in stainless steel plate–fin structure was investigated theoretically. A sequentially coupling finite element analysis (FEA) program was developed to simulate the brazed residual stress distribution, with an emphasis on the material selection for plate–fin metal and filler metal. The properties of three different stainless steel for plate–fin and three different materials for filler metal were incorporated into nine different FEA models. The results show that large residual stresses are generated in brazed joint due to the yield strength mismatching between base metal and filler metal. It is found that the best models are 304 or 347 stainless steel for base metal and BNi4 for filler metal. The residual stresses in the brazed joint are mainly affected by yield strength mismatching. But the yield strength mismatching has little effect on the residual stresses for the base metal.