This paper addresses the weldability of 6 mm thick plates of super-duplex stainless steel by electron beam welding (EBW) process. Microstructure investigations conducted using optical and SE microscopy showed the presence of large ferrite grains with intra- and inter-granular austenite. Ferrite content studies on the weld zone estimated that there is no significant element partitioning between austenite and ferrite phases. Hardness studies portrayed that the weld hardness is found to be greater than the parent metal which is acquainted due to the solid solution strengthening effect. Tensile results corroborated that the joints obtained by EB welding process have better strength than the base metal. A detailed structure-property relationships has also been carried out through point and line mapping EDAX analysis across the weldment to substantiate the discussions. © 2014 The Society of Manufacturing Engineers. Published by Elsevier Ltd. All rights reserved.

Devendranath Ramkumar K

Department of Manufacturing Engineering

School of Mechanical Engineering

Vellore Campus

Arivazhagan N

Mishra D

Vignesh M.K

Raj B.G

Naren S.V

Kumar S.S.

Vellore Institute of Technology (VIT) is a private university located in&nbsp;Tamil Nadu, India. Founded in 1984, as Vellore Engineering College, the institution offers 20 undergraduate, 34 postgraduate, four integrated and four research programs. It has campuses in Vellore, Amravati, Bhopal and Chennai.

VIT is one of the top ranked private universities in India according to NIRF, THE and QS Rankings.&nbsp;Govt. of India has recognized&nbsp;VIT, Vellore as an&nbsp;Institution of Eminence. This has allowed VIT to take independent quality initiatives and move up in world ranking.

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VIT University

Journal of Manufacturing Processes

The fusion zone microstructure and mechanical properties of UNS S32750 joints obtained from gas tungsten arc (GTA), gas metal arc (GMA) and flux cored arc (FCA) welding processes were investigated. The formation of grain boundary, Widmanstätten and intragranular austenite were observed in the fusion zone of the weldments. Electron back scattered diffraction (EBSD) analysis confirmed the presence of chi (ψ) and sigma (σ) phases in the reheated fusion zones of all the weldments. Tensile failures occurred at the fusion zone for all the weldments and the joint efficiency was found to be greater for GTA welds than the others. The number of welding passes and heat input had a significant impact on the ferrite: austenite ratio. FCA weldments experienced inferior notch toughness at both room temperature and sub-zero temperature owing to the prominent amount of secondary austenite and precipitation of intermetallic phases compared to the other weldments. © 2019 Elsevier B.V.

Journal of Materials Processing Technology

Multi-pass arc welding techniques of 12 mm thick super-duplex stainless steel

The present study centered on the effect of welding induced metallurgical changes on the mechanical properties and corrosion behavior of super duplex stainless steel (SDSS) weldments. The weld joints dealt with in the study has been fabricated through use of filler metal ER 2594 using gas tungsten arc welding process. Microstructural investigation in the weldment exhibited the evolution of austenite (gamma) phases in different morphologies such as grain boundary austenite, needle like elongated austenite (Widmanstätten structure) and intragranular austenite particles. Mechanical properties of the weldments were obtained and compared with the parent metal behavior by conducting Vicker's micro hardness assessment, Charpy impact toughness investigation, tensile and three-point bend experiment. Cyclic polarization curves revealed higher corrosion resistance for the weldment than the parent metal in NaCl corrosion medium. Nickel enriched filler ER 2594 led to the nucleation of additional gamma phases in the fusion zone which are electrochemically more resistant than the delta ferrite phases. Moreover, accelerated stress corrosion cracking (SCC) test proved the SCC resistance of both parent metal and weld regions by protecting the surface without nucleation of any kind of fissures or cracks. © 2018 IOP Publishing Ltd.

Materials Research Express

Analysis of structure property relationship of super duplex stainless steel AISI 2507 weldments for severe corrosive environments

This article addresses the joining of 5 mm thick plates of marine grade, super-austenitic (AISI 904L) and super-duplex stainless steels (UNS S32750) by pulsed current gas tungsten arc welding using duplex and austenitic stainless steel fillers. Microstructure studies revealed the segregation of Mo-rich phases in the fusion zone while employing ERNiCrMo-10. Grain coarsening was observed at the heat affected zone (HAZ) of super-duplex stainless steel in both the cases. The study attested that all the tensile failures experienced in the parent metal, AISI 904L for both the weldments. Charpy V-notch impact studies demonstrated that the weldments employing ER2553 were experienced better impact toughness than ERNiCrMo-10 weldments. Further potentiodynamic polarization test in 3.5% NaCl environment was conducted on the coupons of the weldments. The coupons of the weldments were then tested for accelerated corrosion in salt fog chamber for 300 h in 3.5% NaCl environment. This accelerated corrosion test concludes that the parent metal AISI 904L experienced better corrosion resistance than the fusion zones. The investigation also deals with biocorrosion studies of the dissimilar welds of super-austenitic and super-duplex stainless steels. Microbial consortium comprising of six bacterial isolates of which four were Pseudomonas strains P. aeruginosa strain MB1, P. aeruginosa strain MB2, P. fluorescens and P. flavescens, two belonged to Bacillus strains, B. subtilis and B. cereus, for the first time. The bacterial isolates were inoculated in the medium with the presence of the metal coupons. The results were obtained after 15 and 30 days interval and compared with the control to determine the rate of biocorrosion which confirms that there is an accelerated deterioration of the metal coupons by the microbial strains. © 2017

Microstructure, mechanical properties and biocorrosion behavior of dissimilar welds of AISI 904L and UNS S32750

This paper investigates the weldability, metallurgical and mechanical properties of the UNS 32750 super-duplex stainless steels joints by Gas Tungsten Arc Welding (GTAW) employing ER2553 and ERNiCrMo-4 filler metals. Impact and tensile studies envisaged that the weldments employing ER2553 exhibited superior mechanical properties compared to ERNiCrMo-4 weldments. Microstructure studies performed using optical and SEM analysis clearly exhibited the different forms of austenite including widmanstatten austenite on the weld zone employing ER2553 filler. Also the presented results clearly reported the effect of filler metals on strength and toughness during the multi-pass welding. This research article addressed the improvement of tensile and impact strength using appropriate filler wire without obtaining any deleterious phases. © 2014 Elsevier Ltd.

Materials & Design

Characterization of weld strength and impact toughness in the multi-pass welding of super-duplex stainless steel UNS 32750

Experimental investigation on mechanical and metallurgical properties of super duplex stainless steel joints using friction welding process

Research Papers Faculty of Materials Science and Technology Slovak University of Technology

Electron Beam Welding of Duplex Steels with using Heat Treatment

Journal of Materials Science

Toughness and microstructural analysis of superduplex stainless steel joined by plasma arc welding

Microbe Magazine

ASM Participates in CDC-APHL-ASM Meeting on Enteric Disease Testing Issues

Metallurgical and mechanical characterization of electron beam welded super-duplex stainless steel UNS 32750

Journal	Data powered by TypesetJournal of Manufacturing Processes
Publisher	Data powered by TypesetElsevier BV
ISSN	1526-6125
Open Access	No