INVESTIGATION OF THE TRIBOLOGICAL PERFORMANCE OF AlTiN COATED CUTTING TOOLS IN THE MACHINING OF Ti6Al4V TITANIUM ALLOY IN TERMS OF DEMANDED TOOL LIFE

This paper presents a multi-factorial approach to the tool wear evolution when machining Ti6Al4V titanium alloy using high temperature resistant AlTiN coated cutting tools. Machining conditions were selected based on the technological database of machining titanium alloys in aircraft plants. The main novelty of this study is that tool wear progress within the tool life of about 20 min is assessed integrally in terms of mechanical, thermal and tribological process outputs such as cutting forces, cutting energy and cutting temperature. Moreover; the specific cutting energy (SCE), thermal softening effect and friction coefficient (CoF) were determined when recording tool wear curves. Some important research findings concerns distinguishing the three characteristic wear periods with distinctly different values of SCE and CoF In particular, it was revealed that the formation of ceramic protective layer (CPL) on the AlTiN deposited coating influences friction and the tool wear mechanism.