Numerical and experimental study on the profile of metal alloys formed on the inclined substrate by laser cladding

Abstract

During the process of laser cladding, the reaction of laser-powder, interfacial free energy, and gravitational potential energy of molten pool are crucial to the profile and forming quality of the cladding layer. In this research, the laser heat source model and the powder beam model are established to calculate the profile of the cladding layer on the inclined substrate. The model includes the shielding effect of powders on the laser, the reflection of the laser, and the rebound of powder on the inclined substrate. The cladding layer's profile is calculated by the droplet forming method from the point of potential energy in the forming process of the cladding layer. Then, the cellular automata method is used to develop the calculation model. The influence of thermophysical parameters of materials is considered to describe the profile of the cladding layer on substrates with different inclined angles. Experiments were carried out on Stellite6 and Ni60AA powders under different processes to verify the applicability and accuracy of the model for the simulation of the cladding layer. The results show that the profile of the cladding layer calculated by the model is in good agreement with the experimental results. The relative error of the relative cross-sectional area is less than 5%, the relative error of the width is not more than 8%, the relative error of the height is no more than 5%, and the relative error of the peak shift is below 9%, which affirm the possibility of the model to predict the cladding profile of different materials on the substrate with different inclinations. In addition, the model is extended to the simulation of cladding layer on cylindrical substrates. This research can optimize process parameters and improve the forming quality of laser cladding.