Corrosion detection of tinplate cans containing coffee using EIS/EN sensor

WANG Ke(王珂)¹, WANG Ji-hui(王吉会)¹, WANG Hui-hui(王慧慧) ¹, FU Cong-wei(付丛伟) ¹, XIA Da-hai(夏大海)^{1, 2,} ZHENG Xin(郑鑫)³, DANG Li-hua(党丽华)¹, SHI Jiang-bo(石江波)^{1, 4}

(1. School of Materials Science and Engineering, Tianjin University, Tianjin 300072, China;
2. Department of Chemical and Materials Engineering, University of Alberta, Edmonton T6G 2V4, Canada;
3. School of Management, Tianjin University, Tianjin 300072, China;
4. Center for Electrochemical Science and Technology, Department of Materials Science and Engineering,
The Pennsylvania State University, University Park, PA 16802, United States)

Abstract:The corrosion behavior of tinplate cans containing coffee was investigated using novel electrochemical impedance spectroscopy (EIS) and electrochemical noise (EN) sensors. The contents of iron and tin dissolved in cans were detected by inductively coupled plasma mass spectrometer (ICP-MS), and the morphology of corroded surface was observed by optical microscopy and scanning probe microscopy (SPM). The results reveal that the coating resistance, charge transfer resistance and noise resistance decrease with the prolongation of storage time. The iron and tin contents in cans increase with the storage time, while the bump height of coating surface increases from 30 nm to 80 nm during the corrosion of twelve months. The existence of deformation would enhance the corrosion process of tinplate cans. Finally, the corrosion mechanism of tinplate cans in coffee was proposed.

Key words:electrochemistry sensor; electrochemical impedance spectroscopy; electrochemical noise; tinplate can; corrosion