Cailiao Baohu (Dec 2022)
Influence of Different Displacement Amplitudes on High Temperature Fretting Wear Properties of Cobalt-Based Coatings
Abstract
In order to compare the effects of different displacement amplitudes on the fretting wear properties of cobalt-based coatings at high temperature, the CoMoCrSi coating was prepared by the oxygen-assisted supersonic flame spraying process. The high-temperature fretting wear performance test of the coating under different displacement amplitudes was carried out on the self-made high-temperature fretting wear tester.The white light interference scanner was used to measure the wear volume and the wear rate was correspondingly calculated, the scanning electron microscope and energy dispersive spectrometer were used to observe the surface morphology of the wear scar and analyze the element composition, and the surface phases of the wear scar were also analyzed. Results showed that when the displacement amplitudes were 30 μm and 60 μm, the friction coefficient showed a fluctuating upward trend, and the final friction coefficient stabilized at about 0.35 and 0.55. As the displacement amplitude increased, the wear rate was proportional to the wear volume; the wear mechanism was changed from slight plastic change to the mixed mechanism of abrasive wear and adhesive wear, and to the mechanism of abrasive wear accompanying with adhesive wear. The coating in the fretting wear zone was mainly composed of Co7Mo6, Co3Mo and Co3Mo2Si phases.
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