Comparison of tribological behavior of Fe-based metallic glass coatings fabricated by cold spraying and high velocity air fuel spraying

High wear between surfaces may lead to an increase of cost of production in mechanical engineering industry. To solve this problem, Fe-based amorphous coatings prepared using appropriate technology can provide an effective and economical surface protection. In this work, Fe-based metallic glass powders were deposited by cold gas dynamic spraying (CGDS) and high velocity air fuel (HVAF) technology onto 35CrMo steel alloy. Scanning electron microscopy, energy dispersive X-Ray spectroscopy and microhardness measurement were employed to identify the morphology, microstructure, thickness, porosity, elements distribution and hardness of the assprayed coatings, while X-ray diffraction and thermogravimetry and different thermal analysis were applied to clarify the amorphous nature. The dry sliding wear tests were conducted using a ball-on-plate linear tribometer with the counter-face of ZrO2. The worn surface and worn-off debris collected after friction were studied to investigate the wear mechanism. The results display a denser and more uncrystallized structure of CGDS coating than HVAF coating. Moreover, CGDS coating has lower coefficient of friction (COF) and wear rate at different applied loads, indicative of improved wear-resistance.