材料期刊网

The microstructure of Ti3SiC2 ceramic prepared by the in-situ hot pressing/solid-liquid reaction process was investigated by transmission electron microscopy. TiC and SiC were identified to be the main impurity phases in this material. The presence of TIC inclusions in Ti3SiC2 resulted in high density of dislocations within Ti3SiC2 matrix and even interfacial cracking. The SiC impurities were one-dimensional disordered, i.e. with overwhelming of stacking faults and could be distinguished from TiC. Beside the observed impurities imbedded in Ti3SiC2, an interesting phenomenon was that needle-shaped Ti3SiC2 was also observed within TiC grains. The needle-shape Ti3SiC2 grew in TIC following the crystallographic relations of (111) TiC // (0001) Ti3SiC2, (002) TiC // (1(1) over bar 04) Ti3SiC2, and [1(1) over bar0] TiC // [110] Ti3SiC2. Slip trace of basal plane dislocations were observed in Ti3SiC2 and the dislocations pile up at grain boundaries suggesting that significant plastic deformation would be expected in single crystal or coarse-grain material.