Surface micro-texture and tribological properties in longitudinal-torsional ultrasonic-assisted milling Ti2AlNb

Ti2AlNb has much application potential in the aerospace sector thanks to its outstanding material characteristics. Poor wear resistance, however, blocks its development. This study used LTUAM (longitudinal-torsional ultrasonic-assisted milling) to get the surface micro-texture of Ti2AlNb in order to address the issue. By comparing traditional milling (CM), the surface micro-texture and tribological characteristics were studied. On this basis, the kinematic characteristics of the elliptical vibration were explored, introducing the critical condition of the separated pattern. In addition, the torsion-rotation ratio was put forward to understand the separation characteristics. The corresponding finite element model exhibited these kinematic characteristics. The model also looked into how the cutting parameters affected the way surface microtexture was generated. Experimental results indicated that machined surfaces with uniform micro-texture were seen in LTUAM, whereas scratches predominated in CM. The variation of micro-texture and surface roughness was discussed in respect to cutting parameters. It has been demonstrated that a machined surface with uniform micro-texture had superior tribological properties. The friction coefficient under LTUAM was approximately 27.08% less than that in CM.