DIAMOND-LIKE NANOCOMPOSITE COATINGS (A-C-H A-SI-O) FOR TRIBOLOGICAL APPLICATIONS/

Diamond-like nanocomposite (DLN) coatings (a-C:H/a-Si:O) are a particu lar class of modified diamond-like carbon coatings, which can be predo minantly described as two interpenetrating amorphous networks, one net work being a diamond-like a-C:H network and the other a glass-like a-S i:O network. Structural studies have been performed using X-ray diffra ction (XRD) and X-ray photoelectron spectroscopy (XPS). The two-networ k description of the atomic bonding state is investigated by analysing the C-C, C-Si and Si-O contributions to the C 1s and Si 2p XPS photol ines. Tribological properties have been measured using standard ball-o n-disk tests against a steel counterbody at 10N load, yielding a typic al wear factor between 0.5 and 4 x 10(-7) mm(3) Nm(-1). The coefficien t of friction against steel is typically between 0.05 and 0.15, even i n humid air and under water. The low-friction and low-wear DLN coating s, combined with low internal stress and good adhesion, make this type of coatings an excellent candidate for many tribological applications in the automotive, textile, chemical or biomedical industry. (C) 1998 Elsevier Science S.A.