Enhanced wear resistance of additively manufactured copper components reinforced with Stellite 6 and post-processed via laser shock peening: Structural, chemical, hardness, and tribological evaluation
Academic Article in Scopus
Copper coatings, while excellent for thermal and electrical applications, struggle with poor wear resistance in sliding conditions. This study investigates the integration of Stellite 6 (in 5%, 10%, and 20% weight fractions) into copper-based coatings via laser cladding, and the subsequent effects of Laser Shock Peening (LSP) on their structural, mechanical, and tribological properties. Characterization techniques used were X-ray diffraction (XRD), Vickers microhardness tests, optical and SEM-EDS analyses, ball-on-disk tests, profilometry, roughness measurements, residual stress evaluation, and electrical conductivity tests. XRD results indicated a predominant Cu-FCC matrix with Co- and Cr-rich phases introduced by the reinforcement. The addition of Stellite 6 enhanced hardness by 9¿27% and provided more stable wear behavior. LSP further improved these properties, increasing hardness by 40¿50% and inducing compressive residual stresses, thus eliminating initial tensile stresses. When applied to the reinforced coatings, LSP also reduced the coefficient of friction by up to 17.9% and the wear rate by 44¿53%. SEM analysis revealed abrasion and adhesion as the main wear mechanisms, with minor contributions from oxidation. However, electrical conductivity decreased slightly due to the low conductivity of the reinforcement. In summary, the incorporation of Stellite 6 significantly enhanced the performance of the copper coatings, and LSP further magnified these improvements.
