基于交流阻抗和数值积分方法测定腐蚀反应电阻

DETERMINATION OF CORROSION REACTION RESISTANCE BASED ON AC IMPEDANCE AND NUMERICAL INTEGRATION

提出了基于交流阻抗和数值积分原理的二点频率法。通过数值积分计算出腐蚀体系交流阻抗的突部和虚部,求解方程获得腐蚀反应电阻,进而求得腐蚀反应速度。该方法测量时间短,精度高。根据这一改进方法,建立了以TP801B单板计算机与TP801 1232A/D模数转换板及接口电路组成的腐蚀速度测量系统。通过对等效电路及实际体系的测量,并同SOLARTRON1250频响仪测量结果进行比较,证明了该方法的可靠性。由于整个过程仅由单板机控制,设备规模小,造价低,在腐蚀监控领域具有应用价值。

The two frequency method for measurring corrosion reaction resistance based on a. c. impedance and numerical integration has been proposed. The real part and imaginary part of the impedance of corrosion system can be calculated through numerical integration, and the corrosion reaction resistance can be obtained by solving the equations. Then it could be convrted into the corrosion rate. The method has the advantages of short measurement and high precision. According to the principle, a corrosion rate measurement system composed of TP801B single board computer, TPS01 1232A/D converter and the corresponding interface circuit has been set up. Both the module circuit and practical corrosion system were measured by means of the new apparatus. The comparison of the obtained results with the data measured by solartron 1250 FRA and the theoretical values was made. It showed that the proposed method and the newly set up apparatus is reliable. Since the data collection and process is controlled only by a single board computer, the apparatus is compact and low cost. It can be applicable to corrosion monitoring.