Feasibility of Al-TiC coating on AZ91 magnesium alloy by TIG alloying method for tribological application
(1. Department of Mechanical Engineering, National Institute of Technology Rourkela, Rourkela 769008, India;
2. Department of Metallurgical Engineering, Indian Institute of Technology (BHU) Varanasi, Varanasi 221005, India)
2. Department of Metallurgical Engineering, Indian Institute of Technology (BHU) Varanasi, Varanasi 221005, India)
Abstract: An attempt was made to improve the surface properties of the AZ91 Mg alloy through surface alloying of a mixture of Al and TiC with the help of TIG arc as heat source. The microstructural evolution of the alloyed layer on the AZ91 alloy was analysed through SEM and XRD technique. The micro-hardness and the dry sliding wear behaviour were assessed by Vickers micro-hardness tester and pin-on-disc wear test setup, respectively. It is revealed that almost uniform alloyed layer forms on the AZ91 alloy substrate for a specific current and scan speed employed in the present experiments. The alloyed layer exhibits hardness value up to 305 HV0.25, and almost negligible wear as compared to the as-received AZ91 alloy substrate.
Key words: AZ91 magnesium alloy; Al-TiC coating; TIG alloying; micro-hardness; dry sliding wear