Hot corrosion behavior of dissimilar GTA welded Monel 400 and AISI 304

Abstract

This research work reports on the weldability, microstructure, mechanical and hot corrosion properties of manual Gas Tungsten Arc Welded (GTAW) dissimilar combinations of Monel 400 and AISI 304 stainless steel using ENiCrFe-3 filler metal. Bimetallic combinations of Monel 400 and AISI 304 have been characterized by microstructure examination. Mechanical properties include hardness and tensile strength of the weldment has been estimated for the aforementioned filler wire. Further hot corrosion studies have been carried out on the various zones of the weldment by subjecting to cyclic air oxidation and K 2SO4 + NaCl (60%) molten salt environment at 600°C. The corrosion products are systematically characterized using surface analytical techniques. It is a clear indication from the results that the weld region is susceptible to more corrosion in air as well as in the molten salt environment as compared to other regions of the weldment. © 2012 Springer-Verlag.