Mechanical behaviour of flashless hot forged and heat treated TiB-reinforced Ti–6Al–4V composites

Abstract

Ti and its alloys, especially Ti–6Al–4V, are ideal materials for many engineering applications but their wear resistance is generally poor. Literature suggests that TiB is the most promising reinforcement to create Ti-based composites with enhanced wear resistance. In this study, TiB-reinforced Ti–6Al–4V composites with B content of 0, 0.5 and 1 wt% were manufactured via flashless hot forging without and with subsequent solution plus aging heat treatments. From the analysis of the microstructure and mechanical behaviour of the TiB-reinforced Ti–6Al–4V composites, it is found that flashless hot forging in the β phase region seals the residual porosity achieving fully dense materials. The presence of B influences the mechanical behaviour and a more significant strengthening is found for an addition rate of 1 wt% rather than 0.5 wt%. The initial post-forging solution plus aging heat treatment changes the morphology of the microstructural features and, therefore, enhances the mechanical properties whereas the increment of the aging time has lower effect but controls the thermally-activated growth of the TiB particles.