THE EFFECT OF CO₂ (99.5%) AND ARGON (75% : 25%) SHIELDING ASES ON FLUX CORED ARC WELDING (FCAW)

Abstract

The welding process in the oil and gas fabrication industry in Batam continues to develop, with welding serving as a core activity in this sector. Flux Cored Arc Welding (FCAW) has increasingly replaced Shielded Metal Arc Welding (SMAW) due to its higher deposition rate. The shielding gas commonly used in FCAW is CO₂. This study employed two types of shielding gases—pure CO₂ (99.5%) and a mixture of Argon and CO₂ (75% : 25%)—on ASTM A36 carbon steel material. The objective of this research was to evaluate the welding results based on a visual Non-Destructive Test (NDT) for both shielding gases in the 1G welding position, using AWS A5.29/SFA-5.29 E111T1-GM-JH4 filler wire with a 1.2 mm diameter. The results showed that the type of shielding gas significantly affects weld quality. The Argon–CO₂ (75% : 25%) mixture produced a thinner slag, less fume, lower spatter, and a more stable arc compared to pure CO₂ (99.5%).