Laser cladding of Stellite-6 with a coaxial nozzle via modeling and systematic experimental investigations

In this paper, an experimental and simulation analysis is undertaken on laser cladding of Stellite-6 on mild steel and HY80 substrates. A cladding system equipped with a coaxial powder nozzle was used to identify process parameters which would produce both favorable single-track and single-layer clads first on mild steel without the need to identify different process parameters on a per-track basis. Using the parameters from mild steel substrate cladding, a minimal amount of adjustment was shown to provide process parameters to clad Stellite-6 on HY80. Modeling of single-track clads of Stellite-6 on mild steel was performed to gain additional insight into the cladding process and was validated against two single-track conditions. It was shown that a significant amount of variability can exist in the clad geometry depending on the process parameters chosen; thus, the model provides an average portrayal of the process. Finally, based on parameter tuning during the process, cladding was found to be near-optimal when the laser beam diameter was approximately the same diameter as the powder waist diameter.