Regularities of Structure Formation and Physical Properties of Multilayered Composites Based on W, Ta, Hf, Ti, Mo, Cr, Al, and C

New fabrication technique of multilayered composite coatings on inner surface of pipes is developed which is based on ion-plasma sputtering of rod-like target composed of various metals and graphite. It is established that gradient change of elemental composition in the direction Cr -> W -> Mo -> Ta -> Hf -> Ti -> C -> Ti/Al -> C is accompanied by transition from metal mixture carbide to titanium carbide with the grain sizes of similar to 8 - 15 nm. It is found that increase in microhardness up to similar to 26 GPa is caused by additional surface heating by thermal radiation from the ion-heated rod and by elemental composition of the composite layers.