Laser assisted titanium carbide (TiC) coating on AISI304 stainless steel

Abstract

The increasing interest in the betterment of wear resistance and hardness of surfaces that are in contact with abrasives or corrosive materials has accelerated the development of several techniques for creating protective coatings. In this project a search is done on what can be the possible coatings and which are the substrates over which this coating is feasible. TiC was found to be exhibiting a very high melting point and thermal stability, high hardness and excellent wear resistance, low coefficient of friction and high electrical and thermal conductivities and hence chosen to be the best coating available. The substrate that is chosen for coating is AISI304 stainless steel. For the laser treatment pulsed Nd-YAG laser is used. After the laser coating operation the phase changes was studied under SEM. Composition of the laser clad layers was obtained by XRD and the hardness was measured by using Vickers microhardness tester. The hardness of the coating increased to a substantial amount in the range of 650-1900 HV0.1as compared to 190 HV0.1hardness of steel substrate. The coating thickness, the extent of dilution of the stainless steel substrate by TiC and the hardness were primarily dependent upon the laser parameters of power, frequency and the scanning speed.