Progress Report on Inelastic Deformation in Crystalline Non-Metallic Materials

摘要

Densification of polycrystalline TiC was studied during hot-pressing and sintering of powders. Starting powders of Ti plus C, TiC, and TiC plus Ti have been reacted at 1700 to 1835 exp 0 C above the melting point of Ti metal (T/sub m/ = 1675 exp 0 C for Ti). The bulk C:Ti ratio was maintained in the range 0.97 to 0.6 in order to allow the possibility of producing a single phase material. All of the resulting microstructures, examined in the scanning electron microscope, contain press both along the grain boundaries and within the grains. However, the samples fabricated from Ti metal plus TiC contain substantially fewer pores than those produced from TiC powder alone. Debye-Scherrer x-ray diffraction analyses demonstrate that in the TiC plus Ti runs, all of the Ti is transformed to substoichiometric TiC after a few minutes at 1800 exp 0 C. While sintering time and temperature have a small influence on the final density, increasing the weight percent of Ti metal added to TiC dramatically increases the final density and the hardness. (ERA citation 05:026142)