In-situ NbC reinforced In625 claddings by ultrasonic vibration-assisted laser cladding: Mechanical properties and high-temperature oxidation resistance analysis

This study explores how ultrasonic vibration integrated with laser cladding influences the formation and performance of in-situ NbC reinforced In625 claddings, focusing on microstructural characteristics, mechanical properties, and resistance to high-temperature oxidation under varying ultrasonic powers (0–440 W). Ultrasonic vibration notably enhances NbC formation, refines grain size, and improves particle distribution uniformity. Optimal mechanical properties were observed at 330 W, with a 20.2 HV increase in microhardness and a 22.8 % reduction in wear volume, alongside a transition in wear mechanism from adhesive to fatigue wear. High-temperature oxidation tests at 800 °C for 60 h revealed the formation of Cr₂O₃, Nb₂O₅, NiO, and NiCr₂O₄ oxides, with the 330 W setting demonstrating superior oxidation resistance—2.67 mg/cm² wt gain and a 3.65 μm oxide layer, significantly lower than non-ultrasonic samples. However, as the ultrasonic power was further increased to 440 W, the cladding exhibited reduced microhardness, diminished wear resistance, and a decline in its ability to withstand high-temperature oxidation. This indicates that ultrasonic power should not exceed a certain limit, as excessive power can adversely affect the performance of the cladding. These findings underscore the efficacy of ultrasonic vibration in enhancing the performance of NbC reinforced In625 claddings, offering valuable insights for improving high-temperature oxidation resistance.