Investigate the nanowear and frictional behaviour at the intersection of Laser-cladded Stellite-6 composite and Steel substrate

In this study, Co-base Stellite-6 composite is applied onto SS316L steel using laser cladding. The grains in the cladding are ten times smaller than those in the steel substrate, forming a dendritic structure with a thin layer in between that is 1-2 μm thick. X-ray diffraction (XRD) analysis identified W 2 C and Cr 7 C 3 carbides in the cladding, which has more carbide peaks than the original powder. The cladding reaches a maximum nanohardness of 2 GPa at a load of 4000 μN, which decreases to 1.1 GPa at 10000 μN. In comparison, the substrate's hardness is 1.5 GPa at 4000 μN and drops to 1 GPa at 10000 μN. The elastic modulus ranges from 24.00 to 28.41 GPa at 4000 μN, with lower values at higher loads. Wear behavior is examined in three orientations at the intersection: 0°, 45°, and 90° to the cladding direction. The wear depths measured at these angles are 350±10 nm, 460±10 nm, and 640±10 nm, respectively. The lowest wear depth is found at 0° orientation wear track. Compared to the 0° orientation wear track, the 45° and 90°orientation wear tracks suffer with higher wear depth. The shallow slope of wear depth occurred at 0° and 45° orientations wear track whereas the steeper slope of wear depth is found at 90° orientation wear track. The slender shape of worn-out material forms at 0° orientation wear track whereas the patch shape worn-out material formed at 45° and 90° orientations wear track. The 0° and 45° orientations wear track follow the linear frictional path. The friction of 90° orientation wear track decreases from a linear to a parabolic path at the intersection region. The continuous slender worn-out material with linear frictional path forms at 0° orientation wear track. The patch-shaped worn-out material with linear-parabolic frictional path forms at 90° orientation wear track.