Analisis Uji Kekerasan Sambungan Las Smaw Pada Plat Baja Astm A36 Pada Zona Weld Metal, Base Metal, Heat Affected Zone Dengan Perlakuan Heat Treatment Dan Pendinginan Oli Air Udara

Shielded Metal Arc Welding (SMAW) on ASTM A36 steel can cause changes in mechanical properties due to uneven heating and cooling in the weld metal, heat affected zone (HAZ), and base metal regions. This study aims to analyze the effect of heat treatment and different cooling media on the hardness of SMAW welded joints on ASTM A36 steel plates. The specimens were welded using the SMAW method with E6013 electrodes, then heat treated at a temperature of 800°C with a holding time of 1 hour and cooled using oil, water, and air as cooling media. Hardness testing was conducted using the Rockwell method at the weld metal, HAZ, and base metal zones, and the data were analyzed using two- way ANOVA followed by the Tukey test. The results show that the cooling media significantly affect the hardness of the welded joints, where water cooling produces the highest hardness value and air cooling results in the lowest hardness value, with the highest hardness generally occurring in the HAZ region.