PENGARUH KEKERASAN TERHADAP VARIASI HEAT INPUT SAMBUNGAN LAS TAK SEJENIS PADA BAJA KARBON A36 DAN BAJA TAHAN KARAT (AISI 304)

Abstract

Welding is one of the combining methods used to connect metal or metal parts, where this connection utilizes
heat energy from the welding machine used in welding. In the welding process melting occurs between the filler metal
and the welded metal. Welding strength is influenced by many factors including heat input, current strength, filler and
flux, weld speed and cooling rate. This study aims to determine the effect of heat input on the value of hardness in
different materials. In this study, the A36 Low Carbon Steel Plate was connected with 304 Stainless Steel plates using
AWS A5.4: E-309L-16 stainless steel electrodes with SMAW welding system. The test results show that the greater the
welding heat input, the lower the value of hardness. At low heat inputs, the rate of cooling will be faster, so that the
crystal will form martensite on a surface that has hard properties. Whereas in high heat input the cooling rate will be
slower, at room temperature the crystal will form a softer and more ductile perlite.