Finite element analysis for residual stress of TC4/Inconel718 functionally gradient materials produced by laser additive manufacturing

Compared with traditional manufacturing methods, laser additive manufacturing (LAM) has incomparable and huge advantages when preparing functionally gradient materials. However, due to the large temperature gradient and the change of material composition, the residual stress of the structure can be very large, which will seriously affect the mechanical properties of the structure, and cause the structure to bend and crack. In this paper based on the finite element method, the residual stress of TC4/Inconel718 materials widely used in aerospace is studied. And it mainly focuses on the influence of key parameters such as laser energy and material composition of transition layers. The results show that the laser power has a positive correlation with the residual stress of the structure and the change of the residual stress of the contact surface is relatively gentle when the components of the two gradient materials are close. The results obtained are in good agreement with the experiment. The research in this article has reference value for understanding, measuring and reasonably controlling the residual stress of functionally gradient materials by LAM.