自由边界钎料形状对钎焊结构残余应力的影响研究

Investigation of residual stresses distributions with free boundary shape of solder joint in brazing seal

钎料形状是影响钎焊接头残余应力分布的关键因素,已有研究主要是针对理想钎料形状下的残余应力开展的,但针对钎料自由边界形状下的残余应力,少有文献进行相关报道。为探讨二者相互关系,本研究对它们开展了仿真及试验测量。首先对凝固后的自由边界钎料形状进行测量分析,然后利用流体动力学方法对钎料自由界面进行追踪仿真,结果表明:基于流体体积法追踪自由界面,可得到与试验测量较吻合钎料形状。在获得钎料自由边界形状基础上,对钎缝残余应力进行测量分析,并利用有限元方法对残余应力进行仿真计算,结果表明,相对理想钎料形状,自由边界钎料形状下的残余应力与试验测量数据更吻合。本研究结果对于钎焊结构的优化改进提供了更真实的依据。

Bonded dissimilar materials or reinforced ceramic composites, as well as their strengthening and failure mechanisms, had been a topic of growing interest from the past decades to the present. The solder joint shapes were important concern for the residual stress distributions. Many researches had been carried out theoretically and experimentally. These researches give the residual stress distributions with the ideal solder joint shape in the brazing seal.However, actual solder joint shape in these seal systems were rarely considered. For the sake of understanding characteristics of the residual stress distributions more accurately, computational fluid dynamics technique was used to predict the actual solder joint shape. Furthermore, the residual stress distributions resulted from the actual solder solidification behavior were investigated by experimental observation and finite element simulation. The residual stress distributions produced from the actual solder joint were more identical with the experimental results.