INFLUENCE OF ALUMINIUM CONTENT ON THE MACHINABILITY AND SUBSURFACE DEFORMATION OF TITANIUM ALLOYS

摘要

The influence of aluminium content on the mechanical and deformation behaviour of titanium alloys has been explored in the past. With the ever increasing demand for titanium aerospace components, the need to increase production rates, particularly through increased machining is growing rapidly. Thus a mechanistic understanding of the influence of aluminium on the machinability of titanium is important in order to accelerate the development of the next generation of titanium alloys. This paper demonstrates the sensitivity of mechanical twinning and severe plastic deformation levels in the machined surface with respect to aluminium content. Thus this paper will demonstrate a need for a compromise between high production rates and imparted subsurface microstruc-tural deformation or "damage". Deformation behaviour analysis techniques, more traditionally associated with face centred cubic systems have been applied to binary Ti-xAl alloys, in order to demonstrate the effect of aluminium on machinability.