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Based on the lightweight, high strength, rich in mineral resources, as well as easy to recycle a series of advantages, the magnesium alloy material has become an important material in the land, sea and air days \Known as the \Magnesium alloy corrosion resistance and abrasion resistance is poor bottleneck constraints magnesium alloy widely used. Therefore, surface modification technology to improve the surface of magnesium alloy resistance, wear resistance and corrosion resistance overall performance has important practical significance. In this paper, laser melting technology AZ31B magnesium alloy, and the use of of 3kW semiconductor laser processing system for laser melting test, in order to improve wear resistance and corrosion resistance of magnesium alloy; using infrared camera to measure the laser melting distribution and changes of the temperature field in the coagulation process, compared with ANSYS numerical simulation. Using an optical microscope (OM), X-ray diffraction (XRD), and electrochemical corrosion equipment to study the impact of laser processing parameters on the microstructure and properties of laser melting layer, microstructure, physical, electrochemical corrosion and wear performance comparison analysis of the original magnesium alloy and surface modified layer; using ANSYS numerical simulation of the temperature field of the laser melting layer. AZ31B magnesium alloy laser surface melting, melting layer and substrate binding good, no cracks, holes and other defects. Were selected to change these two parameters of the laser power and the scanning speed of magnesium alloy melting layer was analyzed, and found that with the increase of the laser power or the scanning speed decreases, the melt width and the depth of penetration are increased. The melting layer consists of α-Mg and β-Mg17Al12 significant grain refinement than the substrate. The melting layer wear resistance and corrosion resistance are improved, the corrosion potential shifts 0.076 ~ 0.152V, the corrosion current density is reduced by an order of magnitude. In this paper, the real-time monitoring of the temperature field site test, infrared imaging of AZ31B magnesium alloy semiconductor laser. Fused test process using the ANSYS finite element numerical simulation software, its temperature field simulation. Conducted a comparative analysis of the results showed that the simulated temperature results with the experimental test results are relatively close, can instead of using the ANSYS simulation test test. In this paper, the secondary development language APDL finite element temperature field analysis program developed laser melting process, the simulation process automation, given under the conditions of the laser parameters, the dynamic process of the temperature field and temperature distribution , and influence of the melted layer depth, width. Apply to laser melting process of laser the broadband heat source model. And apply ANSYS11.0 software, the establishment of the spot of the laser melting process model, consider the non-linear thermo-physical performance parameters and temperature relationship and initial boundary conditions, the field of laser melting temperature analysis. AZ31B magnesium alloy sheet surface laser melting experiments show that, the the broadband heat source model of the heat source shape and \accuracy and applicability. ANSYS simulation of laser melting temperature field, temperature field model can be established close to the real situation, the use of the the broadband heat source model can calculate get through the comparison of the simulation and the experimental data, and graphics, realistic spot and melting zone section for more reasonable temperature distribution has important practical significance.
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