Machinability of γ-TiAl: A review

Owing to its outstanding mechanical properties, γ-TiAl is desirable materials for cross-generation aero-engines. Nearly 70 years of exploration have made it into the initial application. However, the intrinsic brittleness of γ-TiAl is still a critical obstacle to its large-scale applications. In this context, researchers have made many attempts to study the machinability of γ-TiAl. At present, existing relevant reviews have mostly discussed the processing methods of γ-TiAl. Hence, there is still a lack of a perspective on material properties to analyze the cutting mechanism. Herein, this paper provides the systematic review of such perspectives. Above all, the developmental process, phase transformation, and microstructural evolution of γ-TiAl are discussed, as well as its deformation mechanism at quasi-static. These topics can provide a materials science foundation for the machining of γ-TiAl. And then, the review focuses on the cutting mechanism and surface integrity of γ-TiAl. Moreover, special attention is paid to the microscope deformation mechanism and surface defects evolution of γ-TiAl during cutting. Finally, the review indicates that the high-performance machining technology of γ-TiAl faces challenges and proposes potential future research directions. Solving the difficulties during machining γ-TiAl aero-engine components will accelerate the development of new aero-engines.