Preplaced laser cladding of WC powder on Inconel 718 by laser

Laser processes are widely used for surface properties improvement of parts and components. Laser cladding, using laser as heat source, is an innovative method that can be used for improving surface properties. In this investigation, preplaced technique of laser cladding process of WC powder on Inconel 718 using pulsed Nd:YAG laser is studied. A number of parameters affect the energy density in the process, ultimately affecting the clad quality and geometry. In this study, laser average power, pulse width, focal distance, scanning speed and pre- placement factors are input parameters, while clad dilution, fusion depth, porosity and number of cracks are outputs. It is observed that hard phases are formed on Inconel surface in-situ by laser beam radiation and small changes are made in the substrate properties in a limited zone. Experimental results reveal that energy density of the laser beam is the most important factor affecting the number of cracks in laser cladding process. Also, dilution and porosity are highly affected by laser average power. Furthermore, in multi-pass laser cladding process, 50% overlap between adjacent passes has good results. Experimental results show that by concise arrangement of input parameters, one can achieve to an optimum clad layer. Thus, laser cladding process can efficiently supersede other conventional methods.