Nontraditional energy-assisted mechanical machining of difficult-to-cut materials and components in aerospace community: a comparative analysis

Difficult-to-cut materials such as titanium alloys, high-temperature alloys, metal/ceramic/polymer-matrix composites, hard and brittle materials, as well as geometrically complex components such as thin-walled structures, micro channels and complex surfaces, are widely used in aerospace community. Mechanical machining is the main material removal process and responsible for the vast majority of material removal for aerospace components. Nevertheless, it encounters many problems in terms of severe and rapid tool wear, low machining efficiency, and deteriorated surface integrity. Nontraditional energy-assisted mechanical machining is a hybrid process in which nontraditional energies, e.g., vibration, laser, electric, etc., are applied to improve the machinability of local material and decrease burden of mechanical machining. It provides a feasible and promising way for improving machinability and surface quality, reducing process forces, and prolonging tool life, etc. However, systematic reviews of this technology are lacking with respect to the current research status and development direction. This paper reviews recent progress in nontraditional energy-assisted mechanical machining of difficult-to-cut materials and components in aerospace community. It focuses on the processing principles, material responses under nontraditional energy, resultant forces and temperatures, material removal mechanisms and applications of these processes including vibration-, laser-, electric-, magnetic-, chemical-, cryogenic cooling-, and hybrid nontraditional energies-assisted mechanical machining. Eventually, a comprehensive summary of the principles, advantages and limitations for each hybrid process is provided, and future perspectives on forward design, device development and sustainability of nontraditional energy-assisted mechanical machining processes are discussed.