Investigation of Pitting Corrosion Rate on Micro Plasma Arc Welded Dissimilar Weld Joints of AISI 304 and AISI 430 Stainless Steel Sheets

Abstract

In the present paper investigation is carried out to study pitting corrosion rate of Pulsed Current Micro Plasma Arc welded AISI304 and AISI430 dissimilar joint in three different mediums namely 0.5N NaOH, 3.5N NaCl and 0.5N HCl. Linear Polarization method is used and Tafel are drawn, from which corrosion rates are evaluated in Heat Affected Zone (HAZ) of AISI 304, AISI 430 and at Fusion zone (FZ) of the weld joint. Corrosion pits are studied using Scanning Electron Microscope (SEM) images. It is revealed that AISI 304 is subjected to more corrosion when compared to AISI 430. Corrosion rate is higher in HCl when compared to NaCl and NaOH mediums. Corrosion rate is high at FZ, than HAZ of AISI 304 and AISI 430.