In situ EDXRD measurement of the low transformation temperature effect in laser beam welded stainless steel

This paper investigates the low-transformation-temperature (LTT) effect in austenitic high alloy stainless steel and its influence on strain evolution of laser beam welded specimen. Due to the local heat input high temperature gradients occur between weld seam and base material, which lead to therma...

Full description

Bibliographic Details
Main Authors: F Akyel, M Gamerdinger, K Mäde, K.R.Krishna Murthy, S. Olschok, R. Sharma, U. Reisgen, G. Abreu-Faria, G. Dovzhenko
Format: Article
Language:English
Published: Elsevier 2024-06-01
Series:Journal of Advanced Joining Processes
Subjects:
Online Access:http://www.sciencedirect.com/science/article/pii/S2666330924000104
_version_ 1797324332565790720
author F Akyel
M Gamerdinger
K Mäde
K.R.Krishna Murthy
S. Olschok
R. Sharma
U. Reisgen
G. Abreu-Faria
G. Dovzhenko
author_facet F Akyel
M Gamerdinger
K Mäde
K.R.Krishna Murthy
S. Olschok
R. Sharma
U. Reisgen
G. Abreu-Faria
G. Dovzhenko
author_sort F Akyel
collection DOAJ
description This paper investigates the low-transformation-temperature (LTT) effect in austenitic high alloy stainless steel and its influence on strain evolution of laser beam welded specimen. Due to the local heat input high temperature gradients occur between weld seam and base material, which lead to thermal and transformation induced strains. With targeted alloying in the weld seam the martensitic phase transformation can be shifted to lower temperatures resulting in the so-called Low Transformation Temperature (LTT) effect. This effect uses the volume expansion during the martensitic phase transformation. The delayed volume expansion during martensite phase transformation introduces continuous compressive strains until room temperature is reached and represents a mechanism that can serve to counteract the tensile strains caused by thermal shrinkage. The martensitic microstructure is achieved by dissimilar welding, combining an austenitic stainless steel base material with low alloyed filler wire. With this, the chemical composition of chromium and nickel is diluted, and a martensitic phase transformation occurs. As comparison, similar material combinations of stainless steel base material and conventional welding consumable are performed. In this work, in situ energy-dispersive x-ray diffraction (EDXRD) measurements in the beamline P61A at DESY are performed to investigate the expansion behaviour of martensite based on spectral data. Nine measuring positions are recorded and the strain evolution during welding and cooling of the samples are analysed. It is shown that the martensitic phase transformation changes the strain behaviour and implements compressive strain depending on the distance to the laser spot. It is found that the effect is orientation-dependent and that the highest strain influence is present in welding direction.
first_indexed 2024-03-08T05:54:37Z
format Article
id doaj.art-5ac8fbcf69854b99a31d9026820079f0
institution Directory Open Access Journal
issn 2666-3309
language English
last_indexed 2024-03-08T05:54:37Z
publishDate 2024-06-01
publisher Elsevier
record_format Article
series Journal of Advanced Joining Processes
spelling doaj.art-5ac8fbcf69854b99a31d9026820079f02024-02-05T04:32:11ZengElsevierJournal of Advanced Joining Processes2666-33092024-06-019100193In situ EDXRD measurement of the low transformation temperature effect in laser beam welded stainless steelF Akyel0M Gamerdinger1K Mäde2K.R.Krishna Murthy3S. Olschok4R. Sharma5U. Reisgen6G. Abreu-Faria7G. Dovzhenko8RWTH Aachen University Welding and Joining Institute, Pontstrasse 49, 52062 Aachen, Germany; Corresponding author.RWTH Aachen University Welding and Joining Institute, Pontstrasse 49, 52062 Aachen, GermanyRWTH Aachen University Welding and Joining Institute, Pontstrasse 49, 52062 Aachen, GermanyRWTH Aachen University Welding and Joining Institute, Pontstrasse 49, 52062 Aachen, GermanyRWTH Aachen University Welding and Joining Institute, Pontstrasse 49, 52062 Aachen, GermanyRWTH Aachen University Welding and Joining Institute, Pontstrasse 49, 52062 Aachen, GermanyRWTH Aachen University Welding and Joining Institute, Pontstrasse 49, 52062 Aachen, GermanyHelmholtz Centre Hereon, Institute of Materials Physics, Max-Planck-Straße 1, 21502 Geesthacht, GermanyHelmholtz Centre Hereon, Institute of Materials Physics, Max-Planck-Straße 1, 21502 Geesthacht, GermanyThis paper investigates the low-transformation-temperature (LTT) effect in austenitic high alloy stainless steel and its influence on strain evolution of laser beam welded specimen. Due to the local heat input high temperature gradients occur between weld seam and base material, which lead to thermal and transformation induced strains. With targeted alloying in the weld seam the martensitic phase transformation can be shifted to lower temperatures resulting in the so-called Low Transformation Temperature (LTT) effect. This effect uses the volume expansion during the martensitic phase transformation. The delayed volume expansion during martensite phase transformation introduces continuous compressive strains until room temperature is reached and represents a mechanism that can serve to counteract the tensile strains caused by thermal shrinkage. The martensitic microstructure is achieved by dissimilar welding, combining an austenitic stainless steel base material with low alloyed filler wire. With this, the chemical composition of chromium and nickel is diluted, and a martensitic phase transformation occurs. As comparison, similar material combinations of stainless steel base material and conventional welding consumable are performed. In this work, in situ energy-dispersive x-ray diffraction (EDXRD) measurements in the beamline P61A at DESY are performed to investigate the expansion behaviour of martensite based on spectral data. Nine measuring positions are recorded and the strain evolution during welding and cooling of the samples are analysed. It is shown that the martensitic phase transformation changes the strain behaviour and implements compressive strain depending on the distance to the laser spot. It is found that the effect is orientation-dependent and that the highest strain influence is present in welding direction.http://www.sciencedirect.com/science/article/pii/S2666330924000104Laser beam weldingDissimilar weldingEDXRDIn situ strain measurementLTTPhase transformation
spellingShingle F Akyel
M Gamerdinger
K Mäde
K.R.Krishna Murthy
S. Olschok
R. Sharma
U. Reisgen
G. Abreu-Faria
G. Dovzhenko
In situ EDXRD measurement of the low transformation temperature effect in laser beam welded stainless steel
Journal of Advanced Joining Processes
Laser beam welding
Dissimilar welding
EDXRD
In situ strain measurement
LTT
Phase transformation
title In situ EDXRD measurement of the low transformation temperature effect in laser beam welded stainless steel
title_full In situ EDXRD measurement of the low transformation temperature effect in laser beam welded stainless steel
title_fullStr In situ EDXRD measurement of the low transformation temperature effect in laser beam welded stainless steel
title_full_unstemmed In situ EDXRD measurement of the low transformation temperature effect in laser beam welded stainless steel
title_short In situ EDXRD measurement of the low transformation temperature effect in laser beam welded stainless steel
title_sort in situ edxrd measurement of the low transformation temperature effect in laser beam welded stainless steel
topic Laser beam welding
Dissimilar welding
EDXRD
In situ strain measurement
LTT
Phase transformation
url http://www.sciencedirect.com/science/article/pii/S2666330924000104
work_keys_str_mv AT fakyel insituedxrdmeasurementofthelowtransformationtemperatureeffectinlaserbeamweldedstainlesssteel
AT mgamerdinger insituedxrdmeasurementofthelowtransformationtemperatureeffectinlaserbeamweldedstainlesssteel
AT kmade insituedxrdmeasurementofthelowtransformationtemperatureeffectinlaserbeamweldedstainlesssteel
AT krkrishnamurthy insituedxrdmeasurementofthelowtransformationtemperatureeffectinlaserbeamweldedstainlesssteel
AT solschok insituedxrdmeasurementofthelowtransformationtemperatureeffectinlaserbeamweldedstainlesssteel
AT rsharma insituedxrdmeasurementofthelowtransformationtemperatureeffectinlaserbeamweldedstainlesssteel
AT ureisgen insituedxrdmeasurementofthelowtransformationtemperatureeffectinlaserbeamweldedstainlesssteel
AT gabreufaria insituedxrdmeasurementofthelowtransformationtemperatureeffectinlaserbeamweldedstainlesssteel
AT gdovzhenko insituedxrdmeasurementofthelowtransformationtemperatureeffectinlaserbeamweldedstainlesssteel