Comparison of hardmetal and hard chromium coatings under different tribological conditions

Abstract Electroplated hard chromium and thermal spray hardmetal coatings are widely used in a variety of applications for wear protection of component surfaces. The two protective coating types are tested in direct comparison for tribological conditions of dry abrasive wear (Taber Abraser test) and dry oscillating wear load. Oscillating wear tests are carried out both with hardened 100Cr6 steel and alumina balls as counterbody. Different types of hardmetal coatings are imparted. Besides HVOF sprayed coatings also coatings sprayed by an APS gun with axial powder feed are tested. For HVOF spraying besides standard WC/Co(Cr) feedstock also coarse ( d 50  = 5 μm) and fine carbide feedstock ( d 50  = 0.8 μm) and ultrafine powders, i.e. 2 μm  d