Influence of filler wire on metallurgical, mechanical, and corrosion behaviour of 430 ferritic stainless steel using a fusion welding process

Abstract

The advantage of ferritic stainless steels (FSS’s) over austenitic stainless steels is that they are less expensive alloys. This is due to low or negligible nickel in its alloying element which makes the steel affordable. This type of steel is highly recommended against chloride attack and is also machinable to produce various components for engineering applications. This study examines the effect of various fillers on 430 ferritic stainless steel (FSS). The austenitic (308) and ferritic (410) grades of filler were used to study the weldability, microstructure, mechanical properties, and corrosion resistance using tungsten inert gas welding. The findings showed the emergence of various complex phases in both the weld sample. The sample welded with 410 filler shows acicular ferrite, martensite and austenite. Whereas, austenite and vermicular ferrite are observed in the sample welded with 308 filler. Based on compositions and solidification modes, the mechanical properties of welded joints also vary. It was found that ferritic mode solidified welds dominated in terms of qualities, which was found in 410 filler. In the chloride solution, the behaviour of the pitting corrosion resistance of each weld varied. The sample welded with 410 was superior corrosion resistance. This is due to more δ-ferrite in the weld sample. Whereas, 308 showed poorer resistance against the simulated seawater solution. In 410 welds, a greater degree of sensitization was observed, as compared to 308 welds.