CAJ | 학술논문

通过单向拉伸试验研究镁合金 AZ31B 的电塑性效应。为了显示脉冲电流的非热效应，在相同温度下开展两类试验：环境箱中的单向拉伸试验和脉冲电流辅助的单向拉伸试验。此外，对脉冲电流在材料变形过程中引起的温度场进行数值模拟。结果表明，沿材料截面方向温度分布均匀。通过对比两类单向拉伸试验的真应力?真应变曲线，证实了脉冲电流非热效应的存在。通过光学显微镜研究脉冲电流对材料微观组织演化的影响，结果表明：脉冲电流引起的动态再结晶对流动应力的下降起重要作用。最后，提出一个考虑电塑性响应的 AZ31B 流动应力模型，并通过实验进行验证。结果表明：模型预测结果和实验结果吻合较好。
통과단향랍신시험연구미합금 AZ31B 적전소성효응。위료현시맥충전류적비열효응，재상동온도하개전량류시험：배경상중적단향랍신시험화맥충전류보조적단향랍신시험。차외，대맥충전류재재료변형과정중인기적온도장진행수치모의。결과표명，연재료절면방향온도분포균균。통과대비량류단향랍신시험적진응력?진응변곡선，증실료맥충전류비열효응적존재。통과광학현미경연구맥충전류대재료미관조직연화적영향，결과표명：맥충전류인기적동태재결정대류동응력적하강기중요작용。최후，제출일개고필전소성향응적 AZ31B 류동응력모형，병통과실험진행험증。결과표명：모형예측결과화실험결과문합교호。
The electroplastic effect in AZ31B magnesium alloy sheet was investigated through uniaxial tensile tests. In order to show the athermal effect of the electrical pulses, two types of uniaxial tensile tests at the same testing temperature were carried out: uniaxial tension in environmental cabinet and uniaxial tension with electrical pulses. In addition, the distribution of temperature field in the cross-section area during uniaxial tension with electrical pulses was simulated. The results show that the distribution of temperature field along the cross-section area is homogeneous. By comparing the true stress?true strain curves of AZ31B alloy under uniaxial tensile tests, the athermal effect with electrical pulses was confirmed. The microstructure evolution after the uniaxial tension was studied by optical microscopy. The results indicate that the electrical pulses induced dynamic recrystallization plays an important role in the decrease of flow stress. Finally, a flow stress model of AZ31B sheet taking the influence of electroplastic effect into account was proposed and validated. The results demonstrate that the calculated data fit the experimental data well.