The load-bearing applications of Fe based amorphous coatings are limited due to their poor impact resistance. Here, we have designed an amorphous composite coating reinforced with 20 wt% Al₂O₃ particles that is tougher and more impact resistant than the monolithic amorphous coating. Impact resistance of the coatings was systematically studied by drop-weight impact tests and finite element modelling (FEM). It was found that the hard Al₂O₃ particles in the composite coatings could effectively hinder crack propagation via the formation of micro-cracks inside the Al₂O₃ particles, which absorbs the impact energy. FEM indicates that the Al₂O₃ dispersion acts as the main loading-bearing phase and alleviates the stress concentration in the composite coating, thus suppresses crack initiation and propagation. Furthermore, electrochemical polarization test shows that composite coating remains good corrosion resistance in a 3.5% NaCl solution after impact.

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