On physical and thermochemical properties of high-purity Ti3SiC2

Dense polycrystalline Ti3SiC2 of high purity was successfully fabricated from Ti/Si/2TiC powders by reactive hot-isostatic pressing (HIPing) at 1688 K, 100 MPa for 7.2 ks. A flexural strength of 537 +/- 16 MPa and a Vickers hardness of 4.0 +/- 0.2 GPa. was obtained. The partial pressure of Si is important to maintain the stability of Ti3SiC2 at high temperatures. Ti3SiC2 tended to decompose in N-2, O-2 or C atmosphere at temperatures above 1623 K. The isothermal oxidation kinetics of Ti3SiC2 became parabolic in the temperature range of 1423-1523 K with an activation energy of 295 +/- 20 kJ/mol. At temperatures above 1573 K, the oxidation kinetics became linear. (C) 2002 Elsevier Science B.V, All rights reserved.