中文摘要：

在用高压脉冲电场（pulsed electric field,PEF）技术处理食品的过程中,脉冲电流通过电极-液体表面,引起电化学反应,导致电极腐蚀,从而影响到食品安全和设备运行。利用加速腐蚀实验研究了高压脉冲电场作用下的电极腐蚀规律,重点考察了不同电压幅值、脉宽和溶液电导率对电极腐蚀的影响;测试了溶液中电极材料钛离子质量浓度,以定量表征电极腐蚀程度;得到了腐蚀速度随时间的变化关系曲线。结果表明：PEF作用下电极腐蚀特性可以用传统电路模型来解释;随着电场强度由16.7 kV/cm逐步升至41.7 kV/cm、脉宽由5μs逐步升至20μs,溶液电导率由1μS/cm逐步升至600μS/cm,腐蚀会逐渐加剧,钛离子质量浓度分别由0.466μg/L至2.085μg/L、由0.4μg/L至4.855μg/L和由0.8μg/L至43.4μg/L依次上升;腐蚀由电极表面边缘倒角部分开始逐步向中心区域发展;腐蚀后电极在空气中放置氧化一段时间可使加电时腐蚀速度减慢。最后通过研究电极腐蚀规律提出了抑制或者减少腐蚀的措施。

英文摘要：

During the process of treating food with pulsed electric field（PEF）, the pulsed electric current passes through the electrode-liquid interface inside the treatment chamber. This induces electrochemical reactions that corrode electrode and influence the food security and the facility operation. We studied the corrosion mechanism of electrodes during PEF processes through accelerated corrosion tests, and investigated the influences of the applied voltage, pulse width and solution conductivity on the electrode corrosion, which were scaled by the ion concentration of the electrode material in the sample solution. The relationship between the corrosion rate and the treatment time was also obtained. The results show that the conventional circuit model can explain the electrode corrosion under PEF. The ion concentration increases from 0.466 μg/L to 2.085 μg/L when the applied voltage increased from 16.7 kV/cm to 41.7 kV/cm, from 0.4 μg/L to 4.855 μg/L when the pulse width increases from 5 μs to 20 μs, and from 0.8 μg/L to 43.4 μg/L when the solution conductivity increases from 1 μS/cm to 600 μS/cm. The corrosion of the electrode starts from the chamfer edge and gradually develops to the center area. Oxidizing the corroded electrode in the air can slow down the corrosion. We also proposed some other anti-corrosion measures based on the experimental results.