Plasma Sprayed Alumina Coating on Ti6Al4V Alloy for Orthopaedic Implants: Microstructure and Phase Analysis

Alumina was coated on Ti6Al4V alloy by atmospheric plasma spraying. Surface and cross sectional analysis of the coating by SEM showed that diameter and thickness of splat was greatly influenced by arc current and stand-off distance. In turn, this variation in splat morphology had effect on evolution of α-Al2O3 and γ-Al2O3 phases as revealed by XRD. Higher proportion of required γ-Al2O3 phase was achieved at stand-off distance of 130 mm and arc current of 500A.