Abstract: Despite the vast application of Titanium (Ti-6Al-4 V) alloy in automobile, aerospace and chemical industries, its application in tribological environment is limited due to low hardness and poor wear resistance. This study is aimed to modify the microstructure and thus enhance the microhardness of Ti-6Al-4 V alloy. The alloy was laser cladded with a premixed ratio of Co+Ti/ Ti-6Al-4 V using 4.4 kW continuous wave RofinSinar Nd:YAG laser processing system. Scanning electron microscope (SEM) was used to study the microstructural evolution of new features within the coatings while phase constituents were identified by x-ray diffractometer (XRD). Likewise, the microhardness was measured using Vickers hardness tester machine. With respect to the substrate (Ti6Al4V), the microstructure and hardness of Co-Ti coatings on Ti6Al4V substrate were significantly enhanced. A good metallurgical bonding between the substrate and the resultant coating was obtained. In addition, the intermetallic phases formed were beneficial to the enhanced surface characteristics and hardness properties of the alloy. This work widens the span of viability of Ti6Al4V alloy in advanced engineering applications.
Authors: O.S. Adesina and A.P.I. Popoola
Keywords: Laser Clad Technique; Admixed Co+Ti Powders; Ti-6Al-4 V Alloy, Mircrohardness And Phase Constituents