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This article by \Optical microscope (OM), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and surface profilometer testing techniques by means of material irradiated surface morphology and internal microstructure characterization. And chemical the soaking and micro hardness test after the processing of the 304L stainless steel, corrosion resistance and hardness. Irradiated polycrystalline pure copper surface HCPEB temperature field numerical simulation results show that the material near the surface temperature exceeds the melting point of pure copper, subsurface melts first, the depth of the heat affected zone of approximately 40μm, the the melting start time for 0.4μs a heating rate of up to 109K / s, a cooling rate of 107 K / s magnitude. After three materials in after HCPEB irradiation surface to form a volcano-like craters and microporous. Formation of crater because the sample upon irradiation of the electron beam, subsurface first melted, and with the accumulated energy, the internal volume expansion, the final eruption out, thereby forming volcano-shaped crater. Crater diameter and irradiation using electron beam energy, regardless of the number and irradiation, its diameter increases as the energy increases. Crater density with irradiation energy and irradiation times are related to its density with increasing irradiation number of first and then decreased; several irradiation conditions, its density decreases with increasing radiation energy . Repeatedly under irradiation because the electron beam having a polishing effect, therefore, the surface portion of crater is jettisoned, making crater density decrease. X-ray diffraction analysis showed that a large number of macroscopic residual stress inside of the 304L stainless steel samples treated HCPEB aggregation, such a large residual stress leads to generate a lot of material within oversaturated vacancies, vacancy clusters, and a large number of dislocations, stacking faults, such as one-dimensional and two-dimensional defects. Under the role of the temperature field, these vacancies to move toward the surface along the dislocations and grain boundaries and other defects, and aggregation, and ultimately form a microporous structure in the surface of the material irradiated. By computing the crystal texture coefficients, and by the analysis of transmission electron microscopy proved the presence of (220) crystal plane preferred orientation in 304L stainless steel, and with the increase in the number of irradiation (220) preferred orientation, reduce, (111) preferred orientation increased. After treatment increased the hardness of the surface layer of the 304L stainless steel, refinement of the crystal grains in the sample after treatment was found in the TEM detection, and the increased surface dislocation, which is the main reason for the increase of the hardness of the sample surface. Meanwhile, the corrosion resistance of stainless steel is also improved, and the purification function is to explain one of the reasons that can improve corrosion.
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