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The oxidation of Ti 3 SiC 2 composites (75 at. pct Ti 3 SiC 2 and 25 at. pct TiC x ), prepared via selfpropagating high-temperature synthesis (SHS) and subsequent shock consolidation, has been studied in the range of 1073 to 1573 K in this research. The oxidation kinetics are parabolic with an activation energy of approximately 240 Ϯ 20 kJ/mol. As shown by transmission electron microscopy (TEM) during the very early stages of oxidation, the oxide layer formed contains amorphous SiO 2 and crystalline rutile (TiO 2 ). As oxidation proceeds, a two-layered oxide scale is observed with the outer oxide layer consisting of columnar TiO 2 with trace amounts of SiO 2 and the inner oxide layer being comprised of a mixture of amorphous SiO 2 and fine crystalline TiO 2 . The grain size of the outermost oxide (TiO 2 ) increases with increasing oxidation temperature. The oxidation resistance of the Ti 3 SiC 2 composites prepared by SHS and subsequent shock consolidation is similar to the oxidation of Ti 3 SiC 2 prepared by other means with comparable parabolic constants.

The problem of concentrated force acting on a half-plane made of a power-law creep material is solved analytically. In our approach, the constitutive equation that describes the process of dilatational deformation is omitted. The incomplete material description is used for constructing a solution by bringing the dilatational deformation to zero and, in this manner, making the material incompressible. We find solutions for two cases; one solution is for a linear viscous material, while the second is for a power-law material where the power exponent is equal to three. Solutions of the two problems are found to be very different. While the linear viscous solution is found to be the same as the linear elastic solution, the nonlinear solution is found to be significantly different. This result may give rise to a new experimental technique for characterization of materials with a nonlinear creep behavior.