Abstract: The PVD and CVD coated carbide tools were adopted for highspeed milling of α+β phase titanium alloy TC6. Both the wear pattern and wear mechanism were investigated. The results show that PVD coated tool obtains smaller tool flank wear, longer tool life, and is more suitable for milling of titanium alloy TC6 compared with CVD coated tool under the same cutting condition. The rake face of PVD coated tool mainly suffers adhesive wear and oxidation wear while the flank face suffers border wear. Micro chipping is observed to be the main tool failure ascribed to the negative effects of adhesive wear and border wear on the main cutting edge. In contrast, the tool life of CVD coated tool is shorter; its rake face mainly suffers early microchipping and subsequent crater wear and adhesive wear while its flank face suffers abrasive wear. Coating peeling is confirmed to be the main tool failure for CVD coated tool.

Key words: titanium alloy TC6, high-speed milling, coated tools, wear mechanism