A low-cost machinability approach to accelerate titanium alloy development

Machining is often the most expensive manufacturing process step when producing titanium alloy components. With a move towards higher metal removal rates to meet aircraft orders, it is important to develop rapid, low-cost methods that assess the machinability of titanium alloys and cutting tool combinations. A cost-effective, small-scale methodology has been developed and validated on the industrial scale using high-speed turning to inform on the machining characteristics of commercial and emerging titanium alloys to aid companies in future developments of new titanium alloys and cutting tool materials. The article demonstrates, using the titanium alloys Ti-6Al-4V (Ti-64) and TIMETAL 407® (Ti-407), that a series of early stage, small-scale methods can identify key machinability characteristics including chip form, tool wear, cutting force and surface damage. It can be concluded using these low-cost machinability assessment methods that Ti-407 exhibits better machining properties to Ti-64 for the aspects of machinability focused on cutting forces and tool wear, whereas the contrary is found for subsurface microstructural features and chip control.