Formation of a Nickel Alloy Powder Coating on Thin-Walled Tubes by High-Speed Laser Cladding

Abstract

A 1350-00 nickel alloy powder coating has been deposited on thin-walled 12Kh18N10T stainless steel tubes by high-speed laser cladding. Cladding has been performed using cw radiation from a 10-kW ytterbium fiber laser on a robotic complex. The shapes of the gas–powder jet for Fraunhofer nozzles have been determined. The influence of the laser radiation power and the amount of supplied powder on the structure of the coatings obtained has been evaluated. Metallographic studies of the obtained samples have been carried out. It has been shown that laser cladding under optimal conditions provides an almost nonporous coating with minimal penetration of the base material, ensuring metallurgical fusion. According to the X-ray spectral microanalysis, the chemical composition of the deposited coating hardly differs from the chemical composition of the used powder. The thickness of the deposited layer is adjusted within 100–300 µm in one pass, depending on the deposition modes. The fusion line is identical in structure, which shows a high uniformity of heat input during cladding. The size of the region of thermal influence in the substrate material varies within 50–200 µm, depending on the deposition modes.