Temperature dependence of the tribological properties of laser re-melted Al-Cu-Fe quasicrystalline plasma sprayed coatings

The aim of this study was to investigate the effect of temperature on tribological properties of plasma-sprayed Al-Cu-Fe quasicrystal (QC) coating after laser re-melting treatment. The laser treatment resulted in a more uniform, denser and harder microstructure than that of the as-sprayed coatings. Tribological experiments on the coatings were conducted under reciprocating motion at high frequency in the temperature range from 25 to 650 °C. Remarkable influence of temperature on the friction behavior of the coating was recorded and analyzed. Microstructural analysis indicated that the wear mechanisms of the re-melted QC coatings changed from abrasive wear at room temperature, to adhesive wear at 400 °C and severe adhesive wear at 650 °C owing to the material transfer of the counterpart ball. It was also observed that the ratio of the icosahedral (i)-phase to β-Al₅₀(Fe,Cu)₅₀ phase in the coating was higher after test at 400 °C than that at 650 °C. The variation of the ratio i/β of coating and of the property of the counterpart ball and coating with the temperature are the two main factors influencing the wear mechanisms and value of the friction coefficient.