Evolution of Microstructure in the Heat Affected Zone of S960MC GMAW Weld

Evolution of Microstructure in the Heat Affected Zone of S960MC GMAW Weld

JAMBOR Michał, ULEWICZ Robert, NOVÝ František, BOKŮVKA Otakar, TRŠKO Libor, MIČIAN Miloš, HARMANIAK Daniel

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Abstract. High strength steels were introduced to the welded construction at the beginning of the 21st century. Phase transformation occurring in the heat affected zone of the weld significantly affects the resulting properties of the whole weld. In this study, the Gas Metal Arc Weld (GMAW) of S960MC was investigated with a special emphasis on the microstructural evolution throughout the Heat Affected Zones (HAZ). In the HAZ, three main different sub-zones were recorded. The changes of microstructures in these zones depend on the level of thermal exposure and are varying with distance from the weld metal zone. Microhardness measurements showed a decrease of microhardness in all the examined sub-zones of HAZ. The most significant decrease was recorded in the Intercritical HAZ (ICHAZ), thus it can be stated, together with the tensile tests observations, that the ICHAZ is the most critical part of the HAZ and the whole welded joint.

Keywords
High Strength Steel, S960MC, Welding, Heat Affected Zone

Published online 7/16/2018, 6 pages
Copyright © 2018 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: JAMBOR Michał, ULEWICZ Robert, NOVÝ František, BOKŮVKA Otakar, TRŠKO Libor, MIČIAN Miloš, HARMANIAK Daniel, ‘Evolution of Microstructure in the Heat Affected Zone of S960MC GMAW Weld’, Materials Research Proceedings, Vol. 5, pp 78-83, 2018

DOI: http://dx.doi.org/10.21741/9781945291814-14

The article was published as article 14 of the book Terotechnology

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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