EFFECT OF PROCESS PARAMETERS ON CLADDING WITH STELLITE 6 AND SS316L .POWDERS USING CO2 LASER

Abstract

A series of experiments was performed to investigate the cladding of SS316L and Stellite 6 powders, injected on mild steel and stainless steel substrate, with a 2.0 KW continuous wave CO2 laser. The beam from a continuous CO2 laser was transmitted to the substrate via a step-index glass fibre tube. A number of parameters were investigated such as the scanning speed and powder flow rate to determine their effect on clad formation and integrity. Two different sets of experiments were performed; one involved producing single tracks and the other overlapped tracks. The results indicate that both scanning speed and powder flow rate are critical parameters affecting clad layers characteristics viz, its thickness, width, dilution and cracking. It was found that scanning speed mainly affects the clad width and cracking while powder flow rate controls the clad height and dilution. Microstructure and hardness was also studied and it was observed that the optimum selection of parameters produce finer microstructure resulting in lower dilution in the clad layer, which in- turn can, be beneficial to high temperature wear, oxidation and corrosion properties of the cladding.