Pengaruh Kuat Arus Las Terhadap Sifat Mekanis dan Struktur Mikro Sambungan Las Besi Tuang Kelabu menggunakan Elektroda Nikel dengan Proses Pengelasan SMAW

Abstract

This study aims to determine the effect of welding current on the mechanical properties and microstructure of graycast iron welding joints using nickel electrodes with the SMAW welding process. The research method used wasexperimental study, starting with preparing the workpiece, welding process, making test specimens and testing the weldspecimens. The material to be joined is gray cast iron metal with a butt joint of a 60 ° open seam V open angle. The weldingprocess used uses SMAW with a current of 80 Amperes, 85 Amperes and 90 Amperes. The added material used was anENiFe-Cl type CIN 2 electrode with a diameter of 2.6 mm. Hardness testing was carried out using the Vickers method andmicrostructure testing using an optical microscope. The results showed that the maximum hardness value of the parentmetal occurred at the welding current strength of 85 Amperes, which was 192.17 VHN, then the maximum hardness value ofthe HAZ area occurred at the welding current strength of 85 Amperes, which was 203.46 VHN, while the maximumhardness value of the weld metal was 203.46 VHN. metal) occurred at a welding current of 90 Amperes, which was 211.18VHN. The results of the microstructure observation showed that the matrix formed on the parent metal was pearlite withgraphite in the form of flakes. The micro structure formed in the HAZ area was a martensite structure. Meanwhile, themicrostructure of weld metal consists of an austenite matrix with an even distribution of graphite particles.