13 / 2021-06-21 16:05:45

Microstructure and properties of laser cladding WC/Ni-based composite layer on Al-Si alloy

铝合金；激光熔覆；磨损

The microstructure, dilution ratio, microhardness and wear properties of laser cladding WC/Ni-based composite layer on Al-Si alloy were investigated by scanning electron microscope (SEM), X-ray diffraction (XRD), energy dispersive spectrometer (EDS) and wear testing. In the layer, M₇C₃ and M₂₃C₆ with herringbone and flower-like shape were formed. The microhardness of layer was up to 1100HV, which was 14 times that of the substrate. The dry friction experiment showed that the matrix of the layer had plastic deformation during the friction process. The edge of WC particles appeared shadow, and the main component of shadow was Al and O. When the load was more than 60N, the corundum pair begun to peel off, and WC particles on the friction surface begin to break and fall off. When the load was up to 80N, the corundum pair begun transfer to the layer pair.