PENGARUH DIAMETER ELEKTRODA LAS SMAW PADA BAJA ST 42 TERHADAP KEKUATAN TARIK (Studi Kasus Pegelasan pada Kerangka Bawah Bodi Kapal LCT)

Effect of SMAW Welding Electrode Diameter on ST 42 Steel on Tensile strength (Case Study of Welding on the Underbody Framework of an LCT Ship)

Abstract

Different electrode diameters will provide different heat input to the welding joint due to different amounts of electric current or different amperes. Heat input affects the strength of the welded joint because it affects the microstructure in the heat affected zone (HAZ). Large heat input will cause the HAZ to widen and grain coarsening which ultimately reduces the connection strength, so that electrodes with the same strength but different diameters will produce different connection strengths. After conducting research, the tensile strength of all weld metal from small diameter electrodes will be stronger than that of large diameter electrodes, namely Ø2.6 mm. The width of the heat affected area (HAZ) increases as the heat input increases. 2.85 for diameter 2, 6 mm and 4.15 for diameter 4.0, heat input due to differences in current consumption 15.45% for Ø2.6 mm and 24.25 % for Ø 4.0mm, Elongation of samples welded with small diameter electrodes Ø2.6 mm is greater than samples welded with large diameter electrodes, namely Ø 4.0mm and the connection strength drops greater if using electrodes Ø 4.0mm