Structural design and toughening mechanism of laminated graphene ceramic tool materials.

Based on the finite element model, laminated graphene ceramic tool materials were designed, and the effects of the number of layers and thickness ratio on the residual stress were investigated. According to the simulation design results, laminated Al 2 O 3 –TiB 2 –graphene/Al 2 O 3 –TiN (ATBGN) ceramic tool materials with various structures were prepared using the spark plasma sintering process, and their mechanical properties and microstructures were studied and analyzed. The fracture toughness and flexural strength of ATBGN were 8.65 ± 0.18 MPa m1/2 and 755 ± 25 MPa, respectively, which increased by 66.7% and 21.6%, respectively, compared to those of monolithic Al 2 O 3 –TiB 2 ceramic. Under the synergistic action of graphene and residual compressive stress, the multiscale deflection of cracks and the change in fracture mode occurred, which made the substantial contribution to the improvement in mechanical properties. [ABSTRACT FROM AUTHOR]