Optimization of the Overlap Rate of Multi-track Laser Cladding Based on the Flat-Top Overlapping Model

The overlap rate of multi-track laser cladding determines the surface flatness of the cladding layer. To improve the surface flatness of the cladding layer, an optimization method for the overlap rate of multi-track laser cladding layer based on the flat-top overlapping model is proposed. Firstly, the cross-section profile data of single-track laser cladding are collected, and curve fitting is performed to obtain the optimal fitting cross-section fitting function. Then, the multi-track overlapping model is established based on the optimal fitting function, and the optimal overlap rate model for the multi-track laser cladding is derived theoretically. Finally, the optimization method of the overlap rate is verified experimentally, using 20Cr13 as the substrate, M2, 316L and 15-5PH as the coating powder respectively. The experimental results showed that the flatness of the multi-track cladding layers with different cladding powders is greater than 85% with minor errors. It is shown that the model is helpful to obtain good surface flatness and is suitable for various powders, and the model has good effectiveness and versatility.