Wear behavior and atomic competition mechanism of flexible wear-resistant coating with oxygen-free zone in Ti6Al4V alloy

The flexible wear-resistant coating on Ti6Al4V substrate was successfully fabricated by plasma powder cladding with Al-Si powder. The microstructure, element distribution and phase component of the flexible wear-resistant coating were characterized by the field emission scanning electron microscope (FESEM), energy dispersive spectroscopy (EDS) and the X-ray diffractometer (XRD). The micro-hardness of coating was measured by microhardness tester. The wear-resistance of Al-Si coating was evaluated by sliding friction experiment. The prepared coatings have no cracks and a good metallurgical bonding (MB) with the substrate. The wear-resistance of the coating surface is about twice as much as that of Ti6Al4V substrate. Furthermore, the in-between MB zone has the more excellent wear-resistance (about 7 times). The oxygen free zone can be formed in the MB zone, providing a good toughness for the flexible wear-resistant coating. The wear mode is adhesive wear for the flexible wear-resistant Al-Si coatings. Based on the self-consistent bond length difference (SCBLD) method, the competition among atoms in MB zone as well as the formation mechanism of flexible oxygen free zone is investigated. (c) 2023 The Author(s). Published by Elsevier B.V. This is an open access article under the CC