A Comparative Study on Corrosion Rate of Carbon Steel in <i>NaCl</i> Solution with Continuous and Discontinuous Weight Loss Methods

Abstract

A well-known corrosion parameter is corrosion rate as measured by the electrochemical or the weight-loss methods. The weight loss methods can be measured continuously or intermittently depending on the actual conditions of sample placement and the experimental design. But what distinguishes the measurement method is whether they produce the same corrosion rate value or not. This study aims to study the corrosion rate with a continuous and discontinuous measurement method of weight loss using carbon steel specimens immersed in sodium chloride solution and further compare the two results. For this purpose, 25 sample coupons with the size of 80x23x3.6 mm have been prepared. The measurement of weight loss was carried out on specimens for 10, 20, 30, 40, and 50 days, by immersing the sample in 2 and 3%-wt NaCl, respectively, and one was treated in distilled water according to ASTM G31-72. From the three treatments studied, a percentage of the results was a value that lies between 2.67 and 5.46% with an average value of 4.17%. There is no significantly effect of the data collection method for the three types of the treatment samples immersed for 10 to 50 days in distilled water, 2 and 3%-wt sodium chloride solution.