Progress in research on weak interface structures and performance optimization of machinable ceramics

The current research on machinable ceramics (MC), including mica glass-ceramics, porous ceramics, multiphase ceramics and M_n+1AX_n compounds is reviewed. The effects of weak interface structures on the formation and expansion of cracks during the machining process are analyzed, and the machining mechanism is explained accordingly. The influences of the size, distribution and quantity of the weak interface structures on MC properties are investigated, and then the idea of using the microstructure design of weak interface structures to optimize the performances is discussed. Finally, the main directions for future research of MC are proposed, such as thorough analysis of machining mechanisms, investigation of surface hardening and strengthening techniques, and evaluation of the machinability of ceramics.