Interaction kinetics of tungsten with methane

Kinetics and mechanism of tungsten interaction with methane in the temperature range 1300-2650 deg and pressure range 2-600 Torr have been investigated. Using the methods of metallographic and X-ray phase analyses at the first stage of the interaction only one carbide phase W2C is detected. At the second stage of the interaction diffusion zone becomes two-layer one (WC+W2C), at that the thickness of WC external layer is considerably smaller than the thickness of W2C layer. Under methane pressure exceeding 50 Torr the layer of pyrocarbon is formed on the surface