Title: Visualization and Quantification of Corrosion Processes during Salt Spray Tests
Abstract: Corrosion resistance is one of the most important material properties of metals, and salt spray testing has long been used to evaluate it. In a real environment, it takes a long time for metals to corrode, but this test method uses salt water in spray form to accelerate the corrosion process, allowing evaluation of corrosion resistance in a short period of time. This test has been standardized in many countries and is still used in various fields where metals are involved, but there are still issues to be solved. In this paper, we propose a new apparatus that can automatically observe and quantify the red rust area of steel material, which is not possible with conventional salt spray testers. Through corrosion resistance testing and image analysis using this tester, it is possible to take images of the corrosion process more clearly than with conventional testing methods, and to quantify the change in red rust area using these images. The images of the corrosion indicate the change in surface condition and the growth of the corrosion as red rust continuously. It is also suggested that the change in red rust area can be used as a new method to evaluate corrosion resistance.