Investigating the Effects of Mitigation Techniques on Residual Stress and Microstructure of HSLA Welds

Investigating the Effects of Mitigation Techniques on Residual Stress and Microstructure of HSLA Welds

H. Alipooramirabad, R. Ghomashchi, A. Paradowska, M. Reid

Abstract. Post-weld heat treatment is often required for pressure vessel and piping components for relaxing residual stresses and increasing the resistance to brittle fracture. The present study employed neutron diffraction to examine the effects of conventional post-weld heat treatment (PWHT) on the residual stresses in multi-pass, high-strength, low-alloy-steel, weld joints made by combined Modified Short Arc Welding (MSAW) and Flux Cored Arc welding (FCAW) processes. Residual stresses in excess of yield strength were developed in the Heat Affected Zone (HAZ) and the weld metal of the as-welded specimen (particularly the upper layers of the weld) which were reduced significantly as a result of applying PWHT. Also PWHT lead to substantial changes in the microstructural characteristics of high-strength, low-alloy-steel welds.

Keywords
Microstructural Characterization, HSLA Welds, Neutron Diffraction, PWHT, Residual Stress

Published online 12/22/2016, 6 pages
Copyright © 2016 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: H. Alipooramirabad, R. Ghomashchi, A. Paradowska, M. Reid, ‘Investigating the Effects of Mitigation Techniques on Residual Stress and Microstructure of HSLA Welds’, Materials Research Proceedings, Vol. 2, pp 563-568, 2017

DOI: http://dx.doi.org/10.21741/9781945291173-95

The article was published as article 95 of the book Residual Stresses 2016

Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.

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