S. Tao, Z. Yin, X. Zhou, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, China; C. Ding, Chinese Academy of Sciences, Shanghai Institute of Ceramics, Shanghai, China
Al2O3 coatings with different porosity and Cr2O3 coatings were deposited by atmospheric plasma spraying. The tribological properties of coatings against copper alloy were evaluated with a block-on-ring configuration under severe dry friction conditions at room temperature. Microstructure of coatings was observed using SEM. Some thermo-physical properties of the coatings were measured. Results showed that the thermal diffusivity of Al2O3 coating is higher than that of Cr2O3 coating. Dense Al2O3 coating exhibits lower thermal diffusivity compared with the Al2O3 coating with high porosity. The tribological test results showed that cracking failure occurred in both Cr2O3 and dense Al2O3 coatings. This failure phenomenon is explained in terms of the lower thermal diffusivity of the plasma sprayed Cr2O3 and dense Al2O3 coatings. Keywords: Plasma spraying, ceramic coating, friction and wear, failure mechanism
Summary: Al2O3 coatings with different porosity and Cr2O3 coatings were deposited by atmospheric plasma spraying. The tribological properties of coatings against copper alloy were evaluated with a block-on-ring configuration under severe dry friction conditions at room temperature. Microstructure of coatings was observed using SEM. Some thermo-physical properties of the coatings were measured. Results showed that the thermal diffusivity of Al2O3 coating is higher than that of Cr2O3 coating. Dense Al2O3 coating exhibits lower thermal diffusivity compared with the Al2O3 coating with high porosity. The tribological test results showed that cracking failure occurred in both Cr2O3 and dense Al2O3 coatings. This failure phenomenon is explained in terms of the lower thermal diffusivity of the plasma sprayed Cr2O3 and dense Al2O3 coatings.
