Devendranath Ramkumar K

Department of Manufacturing Engineering

School of Mechanical Engineering

Vellore Campus

Arivazhagan N

Anirudh S

Singh S

Goyal S

Gupta S.K

George J.C

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 Materials Research

This paper investigates the weldability, microstructure and mechanical properties of 5 mm thick Inconel 718 plates obtained by pulsed current gas tungsten arc welding (PCGTAW) using ERNiCu-7, ERNiCrCoMo-1 and ERNiCr-3 fillers. Post weld heat treatment (PWHT) was also carried out at 720 °C/8 h/furnace cooling followed by 620 °C/8 h/air cooling on the weldments. A comparative evaluation based on the microstructure features and mechanical properties of both the as-welded and aged samples were studied. Further this study addressed the combined effect of filler wires and post weld heat treatment on the metallurgical and mechanical properties of the weldments. The studies showed the improvement in tensile strength and drop in impact toughness for all the weldments after direct ageing heat treatment. © 2015 The Society of Manufacturing Engineers. Published by Elsevier Ltd. All rights reserved.

Journal of Manufacturing Processes

Effect of filler wires and direct ageing on the microstructure and mechanical properties in the multi-pass welding of Inconel 718

In the present investigation, an attempt has been made to weld the precipitation hardened Nickel based super alloy Inconel 718 and austenitic stainless steel AISI 316L using Continuous Current Gas Tungsten Arc Welding (CCGTAW) and Pulsed Current Gas Tungsten Arc Welding (PCGTAW) process employing ER2553 and ERNiCu-7 fillers. Microstructure examination using optical and SEM analysis clearly witnessed the formation of unmixed zone at the Heat Affected Zone (HAZ) of Inconel 718 for all the joints. The studies showed the absence of deleterious phases in the CCGTA and PCGTA weldments employing ERNiCu-7. Tensile studies corroborated that the fracture occurred at the parent metal of AISI 316L in all the cases. It was inferred from the present study that PCGTA weldments employing ERNiCu-7 exhibited better metallurgical and mechanical properties. This study articulated the effect of filler metals on the structure-property relationships of the weldments. Â© 2014 Elsevier Ltd.

Materials & Design (1980-2015)

Influence of filler metals and welding techniques on the structure–property relationships of Inconel 718 and AISI 316L dissimilar weldments

Understanding the behavior of weldment at elevated temperatures and especially the corrosion behavior has become an object of scientific investigation recently. Investigation has been carried out on friction welded AISI 4140 and AISI 304 in molten salt of K2SO4–60% NaCl environment at 550, 600 and 650 °C under cyclic condition. The resulted oxide scales in the weldment have been characterized systematically by surface analytical techniques. From the results of the experiments, it is observed that the scale thickness on low alloy steel side was higher than that on stainless steel side. Furthermore, weld interface has been found to be more susceptible to degradation than base metals due to inter diffusion of element across the interface and the formation of intermetallic compound. The influences of welding parameters and the temperature of exposure on the hot corrosion behavior of the weldment were discussed in this paper.

Journal of Materials Science & Technology

Hot Corrosion Behavior of Friction Welded AISI 4140 and AISI 304 in K2SO–60% NaCl Mixture

Dissimilar metal welding involving AISI 304 and Monel 400 finds widespread use in marine and offshore environments for the fabrication of heat exchangers, evaporators, piping and vessels in petrochemical and power generation industries. However studies on the performance of such weldments are scantly found in the literature even though the individual metals have higher corrosion resistance and strength. This paper reports the work carried out on welding of AISI 304 and Monel 400 using Gas Tungsten Arc Welding (GTAW) technique to examine the weldability, mechanical and metallurgical properties. Investigations have been carried out on the hot corrosion behavior of these joints subjected to cyclic air oxidation and K2SO4&nbsp;+&nbsp;NaCl (60%) molten salt environment at 600&nbsp;°C. A comparative analysis was carried out on these weldments for two different filler metals such as E309L and ENiCu-7. The oxide scales formed on the various zones of the weldment have been characterized systematically using surface analytical techniques. Weld zone was found to be more susceptible to degradation than base metals used. The effect of filler materials on the hot corrosion is discussed. The studies reported in this paper would be beneficial for fabricators embracing this type of dissimilar weldments in the petrochemical and power generation industries.

Materials & Design

Effect of filler materials on the performance of gas tungsten arc welded AISI 304 and Monel 400

High temperature corrosion tests were performed on dissimilar friction weldment of low alloy steel and austenitic stainless steel. Test conditions simulated the environment of a biofuel fired boiler. The samples were exposed to synthetic salt containing 40 wt-%K2SO4, 40 wt-%Na 2SO4, 10 wt-%KCl and 10 wt-%NaCl. In the present paper, hot corrosion behaviour of friction welded AISI 4140 and AISI 304 dissimilar materials in molten salt environments at 500, 550 and 600°C was studied. Corrosion was extremely severe on the interface of the dissimilar weldment in molten salt environment. Comparative evaluation was based on the effect of burn-off length and temperature of exposure on hot corrosion behaviour of the dissimilar weldment. Even the interface was attacked through chromium rich phases in hot corrosion environment. The metals formed on the weldment were non-protective. © 2009 Institute of Materials, Minerals and Mining.

Corrosion Engineering, Science and Technology

Hot corrosion studies on dissimilar friction welded low alloy steel and austenitic stainless steel under chlorine containing salt deposits under cyclic conditions

Journal	Data powered by TypesetJournal of Materials Research
Publisher	Data powered by TypesetCambridge University Press (CUP)
ISSN	0884-2914
Open Access	0