Detection of the corrosion degree of beverage cans using a novel electrochemical sensor

Purpose - The purpose of this paper is to report a novel electrochemical sensor designed to detect the corrosion of metal cans used for beverage packaging. Design/methodology/approach - Electrochemical impedance spectroscopy (EIS) and electrochemical noise (EN) were performed to detect the corrosion degree of beverage cans that had been stored for 1 month (named s1), 3 months (named s2), 27 months (named s3) and 43 months (named s4). Findings - The EIS results showed that the EIS plot of s1 samples had not developed to a characteristic of two time-constants, indicating that the coating showed good protective performance. The EIS plots of s2, s3 and s4 showed characteristics of two time-constants, indicating that the organic coatings of s2, s3, and s4 had lost their protective performance. EN results showed that quantities and amplitudes of transient peaks increased with the increasing storage time, indicating that an increasing degree of local corrosion occurred within the cans. A corrosion process for beverage cans is discussed and can be considered in three stages. Originality/value - The designed electrochemical sensor was successfully applied to detect the performance of beverage cans and, further, provided scientific proof to evaluate the shelf life of metal cans for packaging.