THE MECHANICAL AND TRIBOLOGICAL PROPERTIES OF MAGNETRON-SPUTTERED TI-C-H COATINGS

The aim of this work is to determine a correlation between the growth parameters of diamond-like coatings with small amounts of titanium (fr om 10 to 20 at.%) prepared by DC magnetron sputtering of a titanium ta rget in CH4 + Ar gas mixture and their mechanical and tribological pro perties. The composition, microhardness, internal stress, friction coe fficient and adhesion, the evaluation of substrate temperature depende nce on methane flow rate, substrate bias and interlayers formation wer e evaluated. It was found that an increase in the negative substrate b ias voltage to -100 V leads to a considerable increase in the layers' microhardness, which slightly decreases with a further bias increase t o -200 V. The internal stresses decreased at the same conditions due t o substrate temperature growth. The best coatings had a friction coeff icient of 0.12-0.15, a microhardness of 13-15 kN/mm(2) and demonstrate d elastic behaviour and good adhesion. The nature and correlation of t hese properties are discussed. (C) 1998 Elsevier Science S.A.