TiB2-TiC-Al2O3 coating on Aluminium substrate by in-situ laser coating process using pulsed Nd: YAG laser

Abstract

To improve the microhardness and wear resistance of mechanical components, laser coating has been applied to deposit in situ TiB2-TiC-Al2O3 coating on Aluminium substrate using Titanium oxide, Boron carbide and Aluminium as the coating powder. The phase constituents and microstructure of the composite coating were investigated using field emission scanning electron micrograph (SEM) and X-ray diffraction (XRD). Vicker’s Microhardness tester was used to measure the microhardness at the coating cross section. Results show that crack free composite coating with metallurgical bonding to the aluminium substrate obtained. Microstructure analysis confirms the formation of TiB2, TiC and Al2O3 in the coating zone. The microhardness improved significantly in comparison to the as-received Aluminium substrate due to the presence of the hard reinforcement TiB2 and TiC.