传统金属腐蚀实验中，采用失重法来计算材料平均腐蚀速度，难以评价特定介质中材料的真实腐蚀速度与耐腐蚀能力，学生对腐蚀的规律缺乏科学认知。将电化学工作站引入金属腐蚀实验教学中，使得学生掌握如何利用电化学工作站来精确研究金属的腐蚀速度与耐腐蚀能力，可克服上述弊病。采用三电极体系，研究材料制备成工作电极，铂电极为对电极，Ag/ AgCl 电极为参比电极，放入待测介质中，测量开路电位 E - t 曲线，获得腐蚀电位；然后在腐蚀电位下测定塔菲尔图，获得腐蚀电流密度；最后测定交流阻抗谱，获得低频率区实部值。比较与分析腐蚀电位、腐蚀电流密度与低频率区实部值，可以科学客观的评价材料耐腐蚀能力。既提高了实验效果，也提高了学生的学习兴趣。%The average corrosion speed was calculated by the weight loss method during the conventional experimental. Because the method difficultly evaluated the real corrosion speed and anti - corrosion capacity of investigated materials, students could not enough acquire of the corrosion rules. The shortcoming can be overcome by introducing electrochemical station into teaching the experiment on metal corrosion and protect so that students could master how to accurately measure metal rate of corrosion and corrosion resistance. The system in experiments was made of three electrodes,which including working electrode made from materials,counter electrode made of platinum electrode and reference electrode made of Ag/AgCl electrode. The three electrodes were dipped in 5% sodium chloride solution. At first,the E - t curve was plotted under the open circuit potential,the corrosion potential can be obtained;then Tafel curve was plotted under the corrosion potential,the corrosion current density was gained and finally the values of real part in the low frequency range could be obtained by means of analyzing the data from alternating current impedance spectroscopy. The material performance of corrosion resistance was objectively appraised by comparing the corrosion potential,corrosion current density and the values of real part in the low frequency range. The experimental effect was improved greatly and the learning interest of students was intensified.
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