Study on overlap rate and machinability of selected laser melting of maraging steel

In order to investigate the material properties of maraging steel laser additive manufacturing, the cladding layers with different overlap rates on the surface of 18Ni300 were prepared by laser cladding technology, and the morphology, microstructure, and hardness of the cladding layer with different overlap rates were analyzed by various means. The results show that the macroscopic morphology of the cladding layer mainly presents three states under different overlap rates, and the change of overlap rate has no effect on the microstructure in the same area of the cladding layer, but does have an effect on the size of the cladding layer. In the end, the optimum overlap rate is 50%, the surface is smooth, the inner is free from defects, the bonding effect is good, and the metallographic structure is even with high hardness. Milling experiments were carried out on the material after laser additive manufacturing, and the surface morphology was observed, confirming a smooth and well-flattened surface with a roughness of 0.342 μm had been obtained. The suitable overlap rate can make the coating surface smoother, reduce the subsequent processing loss, and improve the production efficiency and powder utilization rate while ensuring the coating quality.