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In recent years, Pulse electron beam surface treatment has been a kind of intensity developed of surface modification. The surface of stainless steel 4Cr13 and steel 40Cr were treated by pulsed electron beam of Russian Solo-type pulse electron beam device. In order to optimize the surface treatment technology and modification mechanism research for the purpose. By means of optical microscope (OM), scanning electron microscopy (SEM), EDS, energy X-ray diffraction techniques, the surface morphology and microstructure structure of samples, which were irradiated by pulse electron beam, was Analyzed. And through the specimen surface roughness, micro-hardness, corrosion resistant, friction and wear resistance test experimental, the material surface treatment technology was obtained and the material surface modification mechanism has been discussed. The experimental results show that:1. For steel 4Cr13 samples irradiated by HCPEB, Caters, three kinds of micro cracks, diffusion particles, diffusion particles and needle deformation structure, are observed on the melted surface. and impurity phase is evoked caters morphology formation main factor. After steel 4Cr13 irradiated by HCPEB of 14 kV, 180 A, 1 Hz and 20 pulses, surface beam melting by center and no crack defects at least pit, hardness and wear corrosion resistance for the significant improvement.2. After HCPEB irradiation, the surface tiny crystalline of steel 40Cr and steel 4Cr13 are compose ofα-phase andγ-phase. With the number of pulses frequency increasing,γ-phase content was increased. And may be due to the directional heat conduction sake, after 20 pulses treatment of the two kinds of steel, the austenite appears (220) single crystal strong diffraction peaks.3. Contrasting initial samples, the surface hardness of treated sample is mainly in an increase trend. Mainly due to the rapid heating makes the electron material surface melting even vaporization and subsequent fast cooling process, which result in the surface grain refinement and serious deformation, and residual stress, grain preferred orientation, the second phase quenching role plays.While concentrated tensile stress caused crack defects, which makes hardness reduced.4. Study of sample steel 40Cr found that transition layers organization columnar crystal structure formation, which could effectively remove surface modified layer and matrix between the crack defects, and improve the structure cohesion. The processed samples sample microhardness and wetness air resistance was improved.
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