采用自主构建的体外模拟流场环境实验平台,通过电化学阻抗谱(EIS)测量、拉伸实验、模拟体液pH值变化测试、SEM观察等方法,对AZ31镁合金在流场环境中的腐蚀行为进行了研究。从腐蚀电化学角度探究了流场中镁合金腐蚀速率与流速的定量关系,并采用ANSYS有限元分析研究了流态与剪切力作用对镁合金不同部位腐蚀差异的影响。结果表明,流场会加速AZ31镁合金的腐蚀,在腐蚀初期,腐蚀电流密度i_(corr)与流场平均流速n之间存在i_(corr)~(-1)=i_c~(-1)+Aν~(-1/2)的关系,其中,ic为不考虑扩散影响时的腐蚀电流密度,A为常数。腐蚀速率随流速增加而增大,且随着腐蚀时间延长,由于腐蚀产物的影响而逐渐偏离i_(corr)~(-1)~n~(-1/2)的线性关系。有限元分析表明,样品不同部位表面流体流态及剪切应力分布不同,局部传质系数K存在显著差异,不同流速下试样边缘部位的传质系数是中间的4~5倍,试样局部腐蚀形貌与剪切应力分布及流态差异相对应。 The self-built in vitro simulated flow field environment experimental platform was used to measure the corrosion behavior of AZ31 magnesium alloy in flow field by means of electrochemical impedance spectroscopy (EIS), tensile test, simulated humus pH change test and SEM observation. Were studied. From the electrochemical corrosion point of view, the relationship between corrosion rate and flow rate of magnesium alloy in flow field was investigated. The influence of fluid flow and shear stress on the corrosion of different parts of magnesium alloy was studied by ANSYS. The results show that the flow field accelerates the corrosion of AZ31 magnesium alloy. At the initial stage of corrosion, there is the relationship between the corr and the average velocity n of the flow field, corr - i = c_ (-1) + Aν ~ (-1/2), where ic is the corrosion current density irrespective of the effect of diffusion, and A is a constant. The corrosion rate increases with the increase of the flow rate, and gradually decreases with the increase of the corrosion time due to the corrosion products. The corrosion rate gradually deviates from the linear relationship of corr ~ (-1) ~ n ~ (-1/2). Finite element analysis shows that the fluid flow and shear stress distribution are different at different parts of the sample, the local mass transfer coefficient K is significantly different, the mass transfer coefficient at the edge of the sample is 4 to 5 times of the middle of the sample at different flow rates, The corrosion morphology corresponds to the distribution of shear stress and the difference in flow regime.