Numerical Simulation and Experimental Research of Laser Cladding Based on Thermo-Mechanical Coupling

The temperature and stress fields of the laser cladding arc numerically simulated by ANSYS birth-death element technique based on the thermo-mechanical indirect coupling nonlinear finite element analysis. The results show that this proposed model is reliable by analyzing the temperature distribution of the finite clement model and the morphological characteristics of the metallographic structure of the experimental specimens. The temperature change of the cladding layer can be divided into two stages. In the first stage, the temperature rises rapidly like a pulse. In the second stage, the temperature drops to the overall temperature of the matrix which likes a hyperbolic shape. On the surface of the cladding layer and along the laser scanning direction, the peaks of the temperature time curves of multiple nodes show a trend of gradual increase. The distribution curves of the residual stress show that there is a greater residual stress at the position near the fixed end along the Z axis in the middle of the bonding surface of the cladding layer and the matrix. The residual stress is distributed symmetrically like the shape of W along the X axis in the middle of the matrix undersurface which is likely to cause stress concentration and mutation at the interface between the cladding layer and the matrix along the Y axis in the middle of the free end.