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 °C 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.