Flank Wear Development in Milling of Inconel 718

Due to the superior mechanical properties such as high temperature strength, high oxidation and corrosion resistance, Nickel-based superalloys are widely used in aerospace industry for critical components subjected to high dynamic stresses at high working temperatures. However, the machinability is very poor because of the characteristic of high work-hardening rate and toughness together with poor thermal conductivity, which poses a greater challenge to manufacturing engineers. In this paper, an experimental study of the tool wear development in milling Inconel 718 is presented. Development of flank wear width and chipped edge width versus machined length under different cutting conditions is introduced, and the associated tool wear mechanisms are analysed. It is believed that abrasion and adhesion are major root-causes of the mechanically activated wear, while thermally activated wear is also a critical factor. The influences of feed rate and cutting speed is also discussed.