Abstract:
This research presented a hot-wire flux-cored arc welding process (Hot-wire FCAW) for carbon steel-based JIS G3101
grade SS400. The hot-wire FCAW was tested at 150 °C and 250 °C and compared with the results of FCAW without heating wire. After
that, the obtained welds were inspected by visual and penetrant testing methods including analyzing the macrostructure characteristics
to assess weld appearance, weld quality, defects, and dilution rate. From the research results, it was found that the heating of FCAW
wire heating during welding resulted in reduced weld width and increased convexity and dilution. It also found that the FCAW without
heating wire and the FCAW with hot wire at 150 °C exhibited porosity and wormhole defects that were larger than the requirements of
international standards. In the case of FCAW with hot-wire at 250 °C, the result showed defect-free with quality weld in both on the weld
surface and the inside of the weld. In addition, this research also presented the effect of square butt welding of non-groove SS400 by
the hot Wire FCAW process. It was found that the welding specimen that went through the process had deep penetration and complete
fusion without any defect. The weld could resist bending force and has good tensile strength with a high joint efficiency of 91%. In
addition, it was found that the quality of non-groove butt weld obtained by Hot Wire FCAW was good and the mechanical properties
meet the requirements according to international standards