CORROSION AND THE EFFECT IN HAZ MICROSTRUCTURES STUDY OF AISI 304 STAINLESS STEEL THAT HAS BEEN WELD WITH A53 CARBON STEEL

• Main Author: Fariz Akram, M
• Format: Final Project
• Language: Indonesia
• Subjects: Teknik (Rekayasa, enjinering dan kegiatan berkaitan)
• Online Access: https://digilib.itb.ac.id/gdl/view/38503
• Institution: Institut Teknologi Bandung

Dissimilar metal welding is used for welding a stainless steel 304 pipe with a low carbon steel A53 pipe. Because of the difference characteristic of the two materials, the effect of heat input in welding is different in each material. That difference causing a problem in each material, if the low carbon steel’s cooling rate is too fast it will form a martensite structure, if the stainless steel’s cooling rate is too slow it will cause a sensitization phenomenon. Sensitization is a phenomenon where Cr react with C and forming a M23C6 carbide in the grain boundary, causing the grain boundary susceptible to corrosion. The purpose of this research is to analyze the corrosion rate of the specimen and to analyze the microstructure of the specimen. Corrosion testing is based on ASTM A262 practice C and the hardness test is using the Micro Vickers methode. Microstructure is observed with optical microscope, it showed that the specimen have sensitized microstructure and formed ferrite phase, after the corrosion testing the specimen have been corroded with intergranular corrosion and eng grain pitting corrosion. From this reaserch, it can be concluded that the higher the heat input in the welding process will cause a faster corrosion rate.