Dissimilar welding behavior of 22% Cr series stainless steel with 316L and its corrosion resistance in modified aggressive environment

Abstract

Superior sustainability in highly aggressive environment makes duplex stainless steels as a futuristic materials and better replacement of austenitic grade, which reflects an inevitability of dissimilar joint in many aggressive environments. In the present work, an attempt has been made to produce dissimilar welds between 22% Cr series duplex 2205 and 316L austenitic stainless steel, employing shielded metal arc welding process, using two different welding parameters (corresponding to current) and studied the microstructural, mechanical properties and corrosion resistance of the weldment. Modified destructive and non-destructive tests were attempted in aggressive environment to assess the intergranular corrosion resistance and pitting characteristics of the weldments. The results of the analysis showed the balanced austenite/ferrite content for both heat inputs. Higher tensile strength and hardness was observed in the low heat input. Intergranular corrosion resistance was improved in high heat input, while, abrupt change in pitting characteristic was observed in the low heat input.