Influence of Cr, Ti and Zr oxides formation on high temperature sliding of NiAl-based plasma spray coatings

摘要

In this study, the tribological characteristics of plasma thermal spray coatings are studied with particular interest on formation and performance of Cr, Ti and Zr oxides under dry sliding at 500 °C with Pin-On-Disc configuration against NiAl. Plain Cr_2O_3, TiO_2 and ZrO_2 coatings were tested to trace the difference between performance of original and in-situ formed oxides. Friction surfaces were examined using SEM and X-ray spectral analyses. The highest wear resistance of NiAl-CrB_2 composite coatings can be related to the formation of Cr_2O_3 During the tribosynthesis process.