TC4/ZQSn10-10扩散连接接头残余应力的数值模拟

对TC4/ZQSn10-10异种材料扩散连接接头处的残余应力分布进行了有限元模拟,并结合组织和应力分布讨论了接头的断裂原因。结果表明,TC4/ZQSn10-10接头的最大残余应力出现在金属间化合物Cu3Ti2上,导致裂纹在Cu3Ti2上萌生;最大剪应力也出现在Cu3Ti2上,最大剪应力的存在使裂纹得到扩展,最终导致接头断裂。通过填加中间层Cu可以缓解接头处的应力分布,使接头强度达到192 MPa,相当于铜合金母材强度的80%以上。

Finite element modeling of residual stresses in the diffusion bonding joints of TC4/ZQSn10-10

The residual stress in the the diffusion bonding joint of TC4/ZQSn10-10 was simulated by finite element modeling(FEM),and the reasons of the joint fracture were analyzed.The simulation results show that the maximum residual stresses concentrate within the brittle metallic compounds Cu3Ti2,where is the position of crack initiation.The maximum shear residual stress,which makes the crack propagate and finally results in the fracture of the joints,also occurs within the Cu3Ti2 phase.The residual stresses are reduced by a Cu interlayer and hence the tensile strength of the joints increases to 192 MPa(above 80% that of the matrix Cu alloy).