Md. Bentzon et al., INTERFACIAL SHEAR-STRENGTH OF DIAMOND-LIKE CARBON COATINGS DEPOSITED ON METALS, DIAMOND AND RELATED MATERIALS, 4(5-6), 1995, pp. 787-790
The material properties of diamond-like carbon (DLC), which make this
material particularly applicable for tribological applications, can on
ly be used if the adhesion of the DLC coating to the substrate is very
strong. Ideally the adhesion should be as strong as the substrate and
/or the coating itself. DLC coatings often exhibit very high internal
compressive stress, increasing the demands for strong adhesion to the
substrate. In this work, DLC was deposited on a steel substrate using
a plasma-enhanced chemical vapor deposition (PECVD) process. In order
to develop processes for the improvement of adhesion, experimental met
hods measuring the interfacial shear strength of a coating to a substr
ate are essential. Unfortunately, these methods are limited, both in n
umber and applicability. In this work, the interfacial shear strength
was measured using the substrate plastic straining technique (D.C. Agr
awal and R. Raj, Acta Metall., 37 (1989) 1265). This method offers an
absolute measurement of the interfacial shear strength. It is conclude
d that the method is easy and fast to perform and is therefore well su
ited for the optimization of process parameters controlling the adhesi
on strength.