PENELITIAN KUALITAS PERMUKAAN PELAT BAJA GALVANIS HASIL PROSES INDUSTRI TERHADAP KETAHANAN KOROSI DALAM LINGKUNGAN AIR GARAM NSKCI)

• Main Author: MAHARDIAN, MAHENDRA
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/1945
• Institution: Institut Teknologi Bandung

The colour degradation on continuous hot-dip galvanizing steel surface products against its corrosion performance and design life was <br /> studied with two kinds of method. Electrochemical tests, using Electrochemical Impedance Spectroscopy (EIS) and Tafel linear polarization, and immersion test were both conducted in 5% sodium chloride (NaCl) solution. Electrochemical test period was 1 hour for each specimen, while immersion test proceed from 1 to 7 days. The <br /> corrosion rate and lifetime of the different colour specimens (the clean and grey spot specimens) was measured, calculated and compared. <br /> The immersion test results showed low corrosion rate on the final day of the test with clean specimen had the lower corrosion rate <br /> compared to grey spot specimen. Corrosion rate measured by Tafel polarization and EIS were slightly higher than the expected value (0,02 - 0,11 mm/yr). Adjustment made from the Tafel polarization curve by considering limited cathodic current effect, gave a better result of corrosion rate compared to Tafel slope determination. The product design life of the clean specimen was longer than the grey spot <br /> specimen.