Microabrasion resistance of nanostructured plasma-sprayed coatings

The aim of this paper is the investigation of the microabrasion resistance of Al2O3-13% TiO2 coatings deposited on SAE-42 steel by atmospheric plasma spray with both conventional and nanomicrostructures. In both the cases of standard and nanostructured coatings, a Ni-Al-Mo 90/5/5 (%wt) bond coat was deposited with the same equipment between substrate and coating to enhance the adherence. The final coating thickness was approximately 500 mu m including the bond coat. The microabrasion test conditions, especially normal load values, were selected to stabilise both grooving and rolling abrasion. This study allows concluding that the specific wear rate of the nanostructured coatings in the two-body regime was similar to the value obtained for the coatings with a conventional microstructure. However, the specific wear rate of the nanostructured coatings decreases 40% with the transition from three-body rolling wear to two-body grooving.