Plasma Cladding and High-Efficient CO2 Laser Cladding of Nickel Based Alloy Powder on the Machinery Parts

The SUS316L stainless steel is widely used as the machinery parts for chemical plant and power plant. In order to improve the wear- and corrosion-resistance quality of parts, usually, the plasma process has been adopted to clad Co-based and Ni-based alloys powder on parts surface of SUS316L stainless steel. In the present work, the CO2 laser (2.4kW-CW) cladding of low residual stress and small distortion, and plasma cladding were investigated to deposit WELPC-6 Nickel alloy powder on the cylindrical prod for power plant. The smooth clad bead was obtained by CO2 laser cladding. The phases of clad layer were investigated by an optical microscope, scanning electron microscopy (SEM), X-ray diffractometer (XRD), electron probe microanalysis (EPMA), and energy-dispersion-spectrometer (EDS). The microstructures of clad layers belong to a hypereutectic structure. Primary phases consist of Cr7C3 and CrB. The eutectic structure consists of γ-(Ni, Fe)+Cr23C6 or γ-(Ni, Fe)+Cr2B. Comparing with the plasma process, the fine microstructures, low dilutions, and high Vickers hardness were obtained by CO2 laser cladding.