基于有限元法和纳米压痕技术的SS304/BNi-2/SS304钎焊接头残余应力分析

Finite element analysis and nanoindentation-based experiment of residual stress of SS304/BNi-2/SS304 stainless steel brazed joints

摘要: 利用有限元软件ABAQUS开发了一个顺次耦合的有限元程序对SS304/BNi-2/SS304T形钎焊接头残余应力进行了数值模拟,并采用纳米压痕试验进行了测量.结果表明,由于304不锈钢与镍基钎料的力学性能的差异导致了钎焊接头残余应力的产生.其最大值出现在钎角部位,裂纹易在该处起裂并扩展,成为最薄弱区域.残余应力沿中缝逐渐减小,其它区域应力分布较均匀.纳米压痕试验采用了Suresh模型,并将此模型下的试验测量结果与有限元结果进行了比较分析,两者吻合较好,从而也验证了有限元模拟的有效性与可靠性.

Abstract: The numerical analysis was implemented on the residual stress of the SS304/BNi-2/SS304 T shape brazed joint by both finite element method(FEM) employing ABAQUS sequentially coupling code and Nanoindentation technology.The results show that the residual stress of the brazed joint produced due to the mechanical property mismatch of the base metal SS304 and the filler BNi-2.The residual stress which can induce the crack initiation and is maximum at the fillet and decreases gradually along the mid-seaming.The other zone is uniformity.So the fillet becomes the weakest area.The Nanoindentation test adopts the Suresh model and the experimental results are corresponded with the FEM and also prove the efficient and reliability of FEM.