Abstract
Applicability of the work is caused by the fact that tungsten was selected as plasma faced material of FR diverter. In this regard, Institute of Atomic Energy implements the work to obtain and study carbide coatings on tungsten. Following methane plasma affect tests under plasma-beam installation conditions, phase composition of samples surface layer is monitored. The X-ray phase analysis is carried out in the Laboratory for Structural and Fuel Materials Testing. Phase state definition is a typical task for X-ray phase analysis. The transformation processes of the tungsten crystal structure may precede the structural transformations occurring when the phase composition changes. Interpretation of the results requires additional information about the analyzed substances. The paper considers variations of phase transformations when interaction between tungsten surface and carbon, structural properties of tungsten were analyzed before and after methane plasma affect. In addition, it refers to peculiarities of their change and calculation. There are calculation results of structural parameters. Presented method is reasonable in terms of the physical basis of modern methods of structural and phase state studying of materials.