Tool wear mechanisms of PCD micro end mill in machining of additive manufactured titanium alloy

The additive manufactured titanium alloy has been extensively applied in medical and aerospace fields; the post-treatment machining is necessary to achieve the machining requirements. In this work, the titanium alloy prepared by SLM process was set as the experimental sample, and the tool wear experiment was carried out by using PCD micro end mill. Tool wear mechanisms and its influence on the machining process were investigated. The experimental results indicated that the irregular arc shape wear zones were produced on the rake face, clearance face, and bottom face, and resulting in a triangle wear zone generated at bottom face. The tool wear area on tool tip and rake face was applied to quantitatively evaluate tool wear process. The dominating wear mechanisms were adhesive wear, abrasive wear, microchipping behavior, and graphitization behavior. The cutting force shows an uptrend with tool wear process, especially the axial force. The maximum milling distance reaches 11,400 mm with tool wear area of 10,120 μm 2 and the cutting resultant force of 20.4N. As the milling distance increases, the surface roughness fluctuation increases, and the material protrusion on the machined surface becomes obvious gradually.