Microstructure and tribocorrosion properties of Fe-based amorphous composite coatings fabricated by laser cladding

In order to solve the problem of poor tribocorrosion resistance of Q235, FeCrMoCBSi Fe-based amorphous composite coatings were fabricated on the surface of Q235 by laser cladding. The microstructure, mechanical properties and tribocorrosion properties of the coating prepared by different laser powers were investigated. The loss behavior of coating and Q235 under the interaction of friction and corrosion was analyzed. It is shown that the coating prepared at 1000 W laser power has relatively high amorphous content and more refined microstructure, so that the microhardness of the coating is 1313HV_0.2, and the loss components of tribocorrosion are less than one order of magnitude of Q235. With the increase of laser power, the amorphous content decreases, making the corrosion and wear resistance worse, and the wear mechanism changes from abrasive wear to adhesive wear, but it is still superior to Q235. In the tribocorrosion experiment, the material loss of tribocorrosion is more serious than that of friction or corrosion. In addition, the different material loss behaviors of the coating and Q235 are revealed, with the loss of the coating dominated by corrosion-induced wear and the material loss of Q235 dominated by friction.