Mechanical properties and mechanism of damage tolerance for Ti3SiC2

Abstract The dense ceramic Ti3SiC2 was fabricated by hot-pressing of TiH2, Si and C powders. The new layered material Ti3SiC2 possesses some unique properties such as low hardness, damage tolerance, and high fracture toughness and flexural strength at room temperature. The flexural strength and fracture toughness of Ti3SiC2, which were measured by three-point bending test, were 427 MPa and 7.20 MPa m1/2, respectively. The mechanisms of this material with the high fracture toughness and strength are discussed based on the observation of microstructure. This layered material has a low hardness of about 4 GPa. The features are observed by scanning electron microscopy (SEM) around hardness indentations suggesting that Ti3SiC2 is a damage-tolerant material able to contain the extent of microdamage at room temperature. The damage tolerance should be due to the multi-absorbing energy mechanisms: grain pull out, grain deformation, delamination, crack deflection and grain buckling.