- Chromium carbide
- Tantalum carbide
- Vanadium carbide
- Zirconium carbide
- Molybdenum carbide
- Titanium carbide
- Boron carbide
- Silicon carbide
The substance under consideration is represented by a gray powder in two crystallographic variants: with cubic (semi-carbide) and hexagonal (monocarbide) lattices. Both modifications are found in the temperature range 2525 - 2755 ° C. The second phase, due to the absence of the homogeneity region when deviating from the stoichiometric composition, forms graphite or transforms into W2C, and at temperatures above 2755 ° C it decomposes to carbon and the first phase. The latter is distinguished by an extensive region of homogeneity, which decreases with decreasing temperature.
Tungsten monocarbide is less hard than semi-carbide, but is capable of forming crystals. The second option is much more temperature and wear resistant. In addition, it is capable of being incorporated into solid solutions.
Tungsten carbide is brittle, but under the influence of load, it exhibits plasticity by sliding stripes.
Crystals of the substance under consideration are characterized by anisotropy of hardness from 13 to 22 GPa on different crystallographic planes.
Compared to steels, tungsten carbide is stronger, but more brittle and less machinable.
Monocarbide has a melting point of 2870 ° C and a boiling point of 6000 ° C. Its molar heat capacity is 35.74 J / (mol- * K), thermal conductivity - 29.33 kJ / mol. The density of this type of tungsten carbide is 15.77 g / cm3.
Despite the fact that the melting point is high, the heat resistance of the material in question is low. This is due to the lack of thermal expansion due to the rigid structure. At the same time, tungsten carbide is characterized by high thermal conductivity. With increasing temperature, this parameter for monocarbide increases twice as fast as for semi-carbide.