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In the context of a lot of research and theoretical analysis, based on the alloy design principles, design Fe-Si-based, high-silicon coating of the Fe-Si-B-based alloy powder, and applying energy ion beam as a heating source, the use of synchronized feeding powder in Q235 low carbon steel substrate prepared on the surface of the ion beam metallurgical silicon coating. Thesis ion beam surface metallurgy process, it is a fast non-equilibrium crystallization process, simultaneously with the plasma torch mobile, alloy weld pool formation and solidification. Continue into the molten bath of the alloy powder to form a melt melting; in the second half of the molten pool, the liquid metal is continuously solidified crystal surface metallurgy process as a phased process of continuous reaction. A detailed analysis of the ion beam surface metallurgy of solidification of the molten pool mechanism, solidification and solidification structure. Application equipped with energy dispersive spectroscopy (EDS) is a scanning electron microscope (SEM), X-ray diffraction instrument (XRD) analysis of Fe-Si-based, Fe-Si-B-based high-silicon coating microstructure characterized, micro component of the transitive phase composition; application of micro hardness tester, vibrating sample magnetometer (VSM) test analysis Department of Fe-Si, Fe-Si-B system of high-silicon coating microhardness and soft magnetic properties, and to explore the painted layer microstructure of the organization and content of alloying elements on the soft magnetic properties; final application TGA/DSC1 simultaneous thermal analyzer test analysis of Fe-Si-B line of high silicon coating resistance to high temperature oxidation resistance preliminary study coating 100 ° C. ~ 1200 ℃ program control air temperature oxidation behavior and mechanism. The results show that: plasma jet surface metallurgy Fe-Si lines high silica coating and the substrate no obvious transition, the Fe-Si-B lines high silica coating and the base body produces obvious transition of white light with plane crystal organization, with the substrate distance of increased from the underlying coarse dendrites transition to the surface of equiaxed grains and fine dendrites. Metallurgical layer is made of α-Fe, of Fe3Si Fe5Si3, FeSi2 with the FEB, Fe5SiB2 phase composition. Coating a silicon content, the higher the boron content (lt; 3.8%), the more uniform and fine coating microstructure, microhardness higher the value, the better the soft magnetic properties. Such as ion beam surface metallurgy Fe-Si-B-based high silicon coating hardness is much higher than the substrate, metallurgy layer to the distribution of the micro-hardness of the base body distribution and silicon element content, silicon-containing 15%, a boron 3.8% 9 # test the sample subsurface microhardness 926HV0.3 the the 9 # coated coercive force 0.031KOe, maximum specific saturation magnetization 101emu / g remaining than the saturation magnetization only 0.76emu / g, rectangular than 0.008, the soft magnetic properties of the most Jia. 9 # 10 # coating oxidation exacerbate the starting temperature is 880 ° C, 962 ° C.
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