Research on microstructure and high-temperature wear properties of laser cladding iron-based coatings

Mechanical components are highly susceptible to wear and tear when operating in harsh environments with high temperatures and heavy loads. Therefore, it is essential to improve the wear resistance of mechanical parts. Laser cladding technology was used to prepare a FeCrSiNiMn iron-based coating on the surface of 2Cr13. The microstructure of the coating and its wear resistance at room temperature and high temperature were studied. The results showed that the average hardness of Fe-based coating was 612.8, 530.6, 492.6, and 471.6 HV0.2 at room temperature, 300 °C, 400 °C, and 500 °C. The average hardness of the coating was more than twice that of the substrate. At room temperature, the average friction coefficient of the substrate and coating was 0.67 and 0.33, and the wear rate was 1.98 × 10−5 and 0.61 × 10−5 mm3/Nm, respectively. The wear resistance of the coating was more than doubled compared to the substrate. Under the high-temperature conditions, the average friction coefficient of the substrate and coating was 0.75 and 0.57, and the wear rate was 5.82 × 10−5 and 3.7 × 10−5 mm3/Nm, respectively. The wear resistance of the coating was about 1.5 times that of the substrate. The wear mechanism of the coating and the substrate at room temperature was abrasive wear and oxidative wear. At high temperatures, the wear mechanism of the coating was adhesive wear and oxidation wear, and the wear mechanism of the substrate was fatigue wear, abrasive wear, and oxidative wear.