Numerical simulation on temperature and stress fields of laser cladded Ni-based coating

In this paper, the software SYSWELD was used to simulate the single track and overlapped laser cladding process. The results show that the molten pool undergoes a rapid heating and cooling process with high superheat degree during the laser cladding. During the single track laser cladding, the peak temperature of the center point on the molten pool surface is highest, reaching 2 589 ℃. In addition, the peak temperature decreases as the distance is far away from the molten pool center. After the single track laser cladding, the cladding coating is in the tensile stress status and the maximum value locates at the interface between the cladding coating and the matrix, while the heat affected zone is in compressive stress. During the laser overlapped cladding process, the first cladding layer experiences tensile stress, but the tensile stress value decreases obviously and the maximum stress locates at the heat affected zone. Furthermore, because of the preheating from the first track to the second one, the peak temperatures of the points on the second cladding coating are higher than those of the single track The maximum tensile stress appears at the bottom of the cladding coating while the heat affected zone is in compressive stress.