Mechanical properties of Mo–Ru thin films with Ni interlayer of different thickness

Noble metal coatings are usually introduced to increase lifetime of glass molding die. In this study, Mo–Ru coatings with Ni interlayer were deposited on tungsten carbide by DC sputtering processes at an elevated temperature of 550 8C to modify the properties in molding die materials. Phase identification was investigated by X-ray diffractometry (XRD). The surface morphology and composition of coatings were evaluated by atomic force microscopy (AFM) and field-emission electron probe microanalyzer (FE-EPMA), respectively. Hardness of the Mo–Ru films was measured by nanoindentation testing. In the aspects of adhesion, the influence on interlayer of different thickness was probed by the scratch test, and the different composition of Mo–Ru resulted in various kinds of fracture configurations. The scratch test exhibited spalling and chipping failure between substrate and layer.