Microstructure and mechanical properties of hot pressed Ti3SiC2/Al2O3

摘要

In this work, Ti3SiC2/Al2O3 composites with various volume contents of Ti3SiC2 were fabricated under different orthogonal processes by vacuum hot pressing sintering. optimized comprehensive mechanical properties and relative density (> 97%) were obtained (the microhardness, flexural strength and fracture toughness reached the values of 16.25 GPa, 536.31 MPa and 9.3 MPa m(1/2), respectively.) when the Al2O3 (60.0 vol %) and Ti3SiC2 (40.0 vol %) were sintered at 1500 degrees C for 0.5 hat 30 MPa, which basically correspond to the best level of after orthogonal calculation. The orientational growth behavior of Ti3SiC2 was further confirmed by EBSD, and temperature was found to play a prominent role in the growth of Ti3SiC2 to some extents, fewer columnar Ti3SiC2 grains were observed at lower temperature and weak decomposition of Ti3SiC2 was observed at 1500 degrees C. Meanwhile, high volume Ti3SiC2 was beneficial to the improvement of mechanical properties for the intrinsical layered structure.