In-situ formation ceramic particles reinforced Fe-based composite coatings produced by ultrasonic assisted laser melting deposition processing

In situ TiB 2 -TiC ceramic particles reinforced Fe-based composite coatings were produced on the surface of 5CrNiMo steel by ultrasonic assisted laser melting deposition processing. Effect of the ultrasonic vibration on the phase structure, distribution of ceramics and wear properties of the coatings were investigated. It was found that ultrasonic vibration did not change the phase structure of the coatings but improved the formation of the coatings. With the increase of ultrasonic vibration output power, microstructure was refined and amount of ceramics increased, as well as distribution of ceramics became more uniform. Wear resistance of the coating produced by 300 W ultrasonic vibration assisted laser melting deposition was about 1.7–2.4 times of that of the coating without ultrasonic vibration, and 3.9–4.6 times higher than that of the substrate. After introducing ultrasonic vibration, wear mechanism of the coating changes from adhesive with abrasive wear to slight abrasive wear.