TiB₂-based ceramics/42CrMo alloy layered gradient material mechanical test and structure design

Based on the previous supergravity field synthesis gradient materials, a TiB2-based ceramic /42CrMo graded material with continuous gradient content of TiB₂-TiC-Fe has been preparatived. XRD, SEM, hardness test and three-point bending strength test on the materials are conducted. And electrical measuring method is used to obtain ceramic substrate part of elasticity modulus.The elastic modulus of the intermediate transition zone is fitted. Finally, an analytical method is used to calculate the stress-strain distribution of the graded material.The results show that the ceramic/alloy phase boundary changes in a continuous gradient, and the hardness decreases in a gradient from ceramic to metal. Three point bending test found that the type of material has similar to the metal plastic deformation features. Therefore, obvious failure delay behavior appears. The elastic modulus of pure ceramic is about 560 GPa. The variation form of elastic modulus in the intermediate transition zone is closer to trigonometric function. The calculated stress indicates that the damage occurs from the bottom of the metal, and then the crack spreads to the top of the ceramic, which is consistent with the experimental phenomenon of this type of material.