Microstructure and mechanical properties of Fe-based amorphous alloy coatings prepared by ultra-high speed laser cladding

•High content Fe-based amorphous coatings without crack have been fabricated using ultra-high-speed laser cladding.•Low dilution ratio and high cooling rate are beneficial to the formation of the amorphous phase.•The crack in the coatings gradually disappears with the coating thickness decreasing. In order to obtain the high content Fe-based amorphous alloy coatings with a small amount of crystallization and few micro-cracks, we introduce a new ultra-high-speed laser cladding technique for fabricating Fe-based amorphous coatings; and study the effects of scanning speed and powder feeding rate on microstructure and properties of the coatings. The experimental results show that with increasing scanning speed, the coating thickness decreases while the amorphous content increases. Simultaneously, the crack in the coatings gradually disappears with the reduction of coating thickness. Metallurgical bonding forms between the amorphous alloy coating and substrate, and the width of the dilution zone is minimal.