Studies on the effect of modes of Metal transfer on mechanical and Metallurgical characteristics of Dual phase stainless steel joints

Abstract

Duplex Stainless Steel (DSS) has equal amounts of ferrite and newlineaustenite, which makes them very resistant to chloride corrosion. The equal newlineproportion of ferrite and austenite, changes with increased heating during newlinewelding. There will be a loss in the imperative characteristics of DSS, and the newlineamount of loss can be minimized by employing appropriate welding newlinemethodologies. To achieve the desired ferrite/austenite balance and hence the newlineproperties of the duplex stainless steel, a specific range of heat input between 0.5 newlinekJ/mm and 2.5 kJ/mm is required. The heat input can be controlled by using newlinedifferent metal transfer modes in the place of constant current (CC) mode of newlinemetal transfer. The modes of metal transfer, such as pulsed current (PC) and newlinesurface tension transfer (STT) modes of metal transfer, are the best methods for newlinecontrolling the weld heat input instead of the typically used constant current newline(CC) mode. The present study aimed to learn about the effects of the CC, PC and newlineSTT modes of FCAW on the microstructure, mechanical, and corrosion newlineproperties of the duplex stainless steel joints. newlineIn the present work, an investigation was conducted to optimize PCFCAW newlineand STT-FCAW process parameters for ferrite content in 2205 Duplex newlinestainless steel joints. The metallurgical, mechanical and corrosion properties of newlinethe flux cored arc welded CC, PC and STT mode specimens were evaluated. newlineFerrite content in the weld metal zone of the DSS joints was measured using newlineFerritescope. Scanning Electron Microscope (SEM) analysis was performed to newlineidentify the ferrite and austenite phases in the FCAW DSS welded specimens. newlineEDAX analysis was carried out to determine the material composition at the newlinethree points of interest in the flux cored arc welded specimens. An EBSD newlineanalysis was performed to discriminate between the dissimilar phases by newlineequating the inter-planar angles taken from the diffraction pattern. newline