Abstract:

Applicability of flux cored wires (FCW) for the welding of duplex and super duplex stainless steel was investigated. Due to the big concerns of FCW in the market, weldability of wires and mechanical properties, pitting corrosion properties and microstructures of weld metals were examined. Not only flux compositions but also the wire homogeneity and wire feeding properties are proved to be significantly important factors on weldability of duplex FCWs.

Pitting corrosion properties of weld metals by FCWs were investigated within the range of PRE 35~ 43. Some factors which affect on impact property and pitting corrosion resistance of FCW weld metal were investigated. Results of microscopic analysis showed no harmful precipitates and no segregation in weld metals even in super duplex grade which contained higher nitrogen and higher molybdenum.