An Experimental and Simulation Study for Powder Injection Multitrack Laser Cladding of P420 Stainless Steel on AISI 1018 Steel for Selected Mechanical Properties

Laser cladding is a rapid physical metallurgy process with a fast heating–cooling cycle, which is used to coat a surface of a metal to enhance the metallurgical properties of the substrate's surface. A fully coupled thermal–metallurgical–mechanical finite element (FE) model was developed to simulate the process of coaxial powder-feed laser cladding for selected overlap conditions and employed to predict the mechanical properties of the clad and substrate materials, as well as distortions and residual stresses. The numerical model is validated by comparing the Vickers microhardness measurements, melt pool dimensions, and heat-affected zone (HAZ) geometry from experimental specimens' cross sectioning. The study was conducted to investigate the temperature field evolution, thermal cycling characteristics, and the effect of deposition directions and overlapping conditions on the microhardness properties of multitrack laser cladding. This study employed P420 stainless steel clad powder on a medium carbon structural steel plate substrate. The study was carried out on three case studies of multitrack bead specimens with 40%, 50%, and 60% overlap. The results provide relevant information for process planning decisions and present a baseline to the downstream process planning optimization.