Journal of Materials Science, Vol.29, No.2, 534-543, 1994
Structural and Mechanical-Properties of TiB2 and TiC Prepared by Self-Propagating High-Temperature Synthesis/Dynamic Compaction
Titanium-diboride and titanium-carbide compacts with diameters of 100 mm and thicknesses of 25 mm were fabricated by self-propagating high-temperature synthesis/dynamic compaction (SHS/DC) of the elemental powders. Under the best conditions, the densities were greater than 99% and 96.8% of the theoretical densities for TiB2 and TiC, respectively. The microhardness, compressive strength, and elastic modulus of the TiB2 prepared by the SHS/DC method were comparable to reported values for hot-pressed TiB2. While the microhardness and elastic modulus of the TIC compacts were comparable to those for hot-pressed TiC, the compressive strength was lower due to extensive cracks in the compacts. The TiB2 prepared using a low-purity boron powder (1-5% carbon impurity) compacted to higher densities and had less cracking than that prepared using a high-purity boron powder (0.2% carbon). This result could have an impact on the cost of producing TiB2/TiC structural components by the SHS/DC process.