Numerical simulation of residual stress in YG8/GH4169 dissimilar material brazed joints

Drilling sampling is the preferred method to achieve lunar soil sample collection. To address the issue of high residual stress and poor connection quality in dissimilar material brazed joints within drilling sampling tools, this paper uses ANSYS finite element software as a platform and a numerical simulation method to study the distribution of residual stress in a YG8/GH4169 brazed joint, as well as the influence of adding Cu and Mo interlayers on the residual stress in the joint. The results indicate that there is a great deal of residual stress in the brazed joint of cemented carbide/superalloy. The dangerous area of stress concentration is the vertex of the cemented carbide near the welding seam, with a maximum axial residual stress of about 1304 MPa. Adding Cu and Mo interlayers can effectively alleviate residual stress in the joint. When the thickness of the interlayers is less than 0.6 mm, Cu has a better relieving effect on residual stress in the joint. When the thickness of the interlayers is greater than 0.6 mm, Mo has a better relieving effect. When Cu and Mo are used as interlayers, the optimal thickness for relieving residual stress in the joint is around 1.0 mm. The experimental results of residual stress in dissimilar materials brazed joints are basically consistent with the numerical simulation results.