Microstructure and mechanical properties of W-C:H coatings deposited by pulsed reactive magnetron sputtering

► Tungsten containing carbon coatings were deposited by pulsed magnetron sputtering. ► The coatings show multilayer structure with alternately high and low tungsten contents. ► HREM analysis shows crystalline WC-type precipitations of about 1-2 nm in size. ► A correlation between H3/E2 ratio and toughness as well as adhesion was found. ► Formation of transition tribo-layer at the counterpart is discussed.