Tungsten Carbide Fitting Physical Properties

Tungsten carbide fitting is high melting, 2,870 °C (5,200 °F), extremely hard (~9 Mohs scale, 1700–2400 Vickers number) with low electrical resistivity (~2×10−7 Ohm·m), comparable with that of some metals.
WC is readily wetted by both molten nickel and cobalt. Investigation of the phase diagram of the W-C-Co system shows that WC and Co form a pseudo binary eutectic. The phase diagram also shows that there are so-called η-carbides with composition (W,Co)6C that can be formed and the fact that these phases are brittle is the reason why control of the carbon content in WC-Co hard metals is important. 

Tungsten Carbide Fitting Chemical Properties

There are two well characterized compounds of tungsten and carbon, WC and tungsten semi carbide, W2C. Both compounds may be present in coatings and the proportions can depend on the coating method.
At high temperatures WC decomposes to tungsten and carbon and this can occur during high-temperature thermal spray, e.g., in high velocity oxygen fuel (HVOF) and high energy plasma (HEP) methods.
Oxidation of WC starts at 500–600 °C. It is resistant to acids and is only attacked by hydrofluoric acid/nitric acid (HF/HNO3) mixtures above room temperature. It reacts with fluorine gas at room temperature and chlorine above 400 °C (752 °F) and is uncreative to dry H2 up to its melting point. WC dissolves readily in diluted hydrogen peroxide.