Obtaining Superhard Coatings of Cubic Tungsten Carbide under High-speed Plasma Spraying

Cubic tungsten carbide WC
_1-x
is one of the most poorly studied phases of the W-C system due to the difficulty of obtaining WC
_1-x
by most known methods and its instability under heating. This makes it difficult to obtain WC
_1-x
in bulk form and measure its physical and mechanical properties. In this work, cubic tungsten carbide was synthesized in the form of a coating by the plasma dynamic method. The process was implemented under highspeed spraying of an electric discharge W-C plasma on copper and titanium substrates. As a result, the coating has a sandwich structure Cu-WC
_1-x
-Cu substrate) or (TiC+WC
_1-x
)-Ti- (WC
_1-x
+TiC)-Ti(substrate) with a thickness of the WC
_1-x
layer up to ~10 μm, Direct measurements of WC
_1-x
mechanical properties were carried out for the first time. The maximum values of nanohardness and Young's modulus of the WC
_1-x
layer are
_Hv
= 31.0±0.8 and
_E
=
310±12 GPa respectively.