THE EFFECT OF TIME VARIATION ON CORROSION BEHAVIOR ASTM A36 IN SWAMP WATER FROM THE VILLAGE OF RAMBUTAN SOUTH SUMATRA PROVINCE, INDONESIA

Most of Indonesia's land is covered in swamps, and many infrastructure projects, including bridge construction, factory construction, and pipe installation, are completed in swampy environments. Swamp water typically has a high acid content and higher than normal concentrations of sulfates and chlorides, which are known to be more active in producing corrosion under normal conditions. This study aims to analyze and understand the corrosion rate and changes in the physical and mechanical properties of ASTM A36 steel that has undergone quenching heat treatment. Compared to steel ASTM A36 as received immersion in corrosive media using swamp water from The Village of Rambutan, South Sumatra Province, which has a pH of 3.00 with variations in immersion time of 48 hours, 96 hours, and 144 hours. The method used to determine the hardness value was the Brinell method, the corrosion rate was determined by the weight loss method, and SEM tests were carried out to determine the surface morphology of the specimens after immersion and XRD tests. The results showed that ASTM A36 steel specimens with quenching heat treatment had a higher hardness value than the as-received specimens; the greatest value was obtained in specimens with quenching treatment with immersion time. 48 hours, which is 497.97 BHN. The immersion test results showed that the highest corrosion rate occurred in the as-received specimen with a 144-hour immersion time of 17.6 mpy. Observation of the microstructure on the surface of the specimen found uniform corrosion and fitting corrosion; this was evidenced by the detection of iron oxide (Fe2O3), known as iron rust which is brownish-yellow in XRD testing.