【摘要】 采用离子与固体相互作用理论和辐照增强扩散理论建立了金属离子高温注入的传质模型,利用有效形成热理论建立了金属离子高温注入合成金属间化合物相形成预测模型。采用MEEVA源进行了Al离子高温注入镁合金AZ31表面改性。利用Rutherford背散射和X射线衍射方法分析了注入改性层的成分与相结构,利用动电位阳极极化测量及摩擦磨损试验测定了注入改性镁合金AZ31的耐腐蚀、抗磨损性能。计算的Al离子高温注入镁合金AZ31的成分—深度分布及金属间化合物Al12Mg17形成规律与试验测量结果相符。注入剂量为6×1016ions·cm-2的Al离子高温试样,腐蚀电位和孔蚀击穿电位分别达到-1180mV(SCE)和-480mV(SCE),维钝电流密度较原始镁合金试样的电流密度约降低1个数量级。高温注入镁合金试样的磨痕较窄,磨损量较原始试样减小约20%。Al离子高温注入显著改善了镁合金AZ31的耐腐蚀、抗磨损性能。更多还原

【Abstract】 A mass transfer model is built up for metal ion implantation at elevated temperatures based on the transport of ions in solid and the radiation enhanced diffusion theory, and the effective formation heat model is built to predict the intermetallics formation during the ion implantation by introducing. The surface modification of AZ31 magnesium alloy by Al ion implanting at elevated temperature is carried out in a MEVVA 80-10 ion implantation system. The concentration-depth profiles of implanted Al and the microstructure of implanted samples are analyzed by Rutherford backscattering spectrometry and x-ray diffraction, respectively. The calculated concentration-depth profiles and the predicted formation of Mg17Al12 intermetalics are consistent with the measurement results. The AZ31 magnesium alloy samples implanted with an implantation dose of 6×1016 ions·cm-2 have the highest corrosion potential of -1 180 mV (SCE)and pitting corrosion breakdown potential of -480 mV (SCE). Their passive current density is reduced correspondently by about one order that of the original sample. The worn grooves observed on the Al ion implanted samples at elevated temperature is narrow with a reduced wear rate of about 20 % that of the original sample. The Al ion implantation into AZ31 magnesium alloys at elevated temperature improves significantly performance of anti-corrosion and wear-resistance.更多还原