Effect of induction heat treatment on residual stress distribution of components fabricated by wire arc additive manufacturing

Abstract

Wire Arc Additive Manufacture (WAAM) has been shown to be suitable for manufacturing large-scale components due to its low cost and high material deposition rate. However, the residual stresses resulting from the WAAM process affect the practical application of WAAM parts as it often leads to unacceptable distortions and degradation of mechanical properties. In this study, induction heating was applied as a heat treatment method to improve the stress distribution in WAAM parts. The heat treatment method can perform local in-situ heat treatment on the surface of parts with different structures and can be used as an intermediate process of WAAM or hybrid manufacturing processes with high flexibility. Moreover, considering the complex relationship between stress changes and components' shape, WAAM process parameters, and heat treatment, a finite element model is established to simulate the thermal and stress field during the whole process of WAAM and induction heating. Based on the simulation results, combined with the components' structural characteristics and application requirements, the method can change the stress distribution according to the design. The method's effectiveness is verified through thermal and stress experiments on the WAAM part of the C-beam structure. The induction heat treatment plan designed according to the predicted stress distribution results alleviated the stress concentration and improved the stress distribution in the component.