Microstructure and Friction Characteristics of SiC/Ni60 Coatings by Different Directed Energy Deposition Laser Powers

Abstract The microstructure and tribological characteristics of SiC/Ni60 composite coatings manufactured using directed energy deposition (DED) technology are investigated. The influence of different laser powers on the composites is studied. The evolution characteristics of the microstructure, the stepped variation pattern of microhardness, and the formation mechanism of wear resistance induced by different laser powers are observed in SiC/Ni60 composite coatings. Laser power variations emerged as crucial factors for improving the structure and performance of the composites. The relationship between microstructure, phase identification, and laser power is clarified using scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), electron back-scattered diffraction (EBSD), and X-ray diffractometer (XRD). The best laser power is determined to be 3000 W based on microhardness and tribological characteristics. Additionally, the friction coefficient, wear rate, and wear behavior provide insights into the tribological features. Appropriate laser power parameters can suppress severe abrasive and adhesive wear and reduce the area of oxidative wear, resulting in a 51.99% reduction in wear rate. From the results obtained, it is evident that selecting the appropriate laser power provides a valuable direction for improving the performance of the composite coatings. The present work is expected to be applied to components such as crankshafts, where enhanced wear resistance is required.