In situ analysis of the strain evolution during welding using low transformation temperature filler materials

ABSTRACT

Compared to conventional welding consumables using low transformation temperature (LTT) filler materials is an innovative method to mitigate tensile residual stresses due to delayed martensite transformation of the weld. For the effective usage of LTT filler materials, a deeper understanding of the complex processes that lead to the final residual stress state during multi-pass welding is necessary. Transformation kinetics and the strain evolution of multi-pass welds during welding were investigated in situ at the beamline HEMS@PETRAIII, Germany. Compared to conventional welds, the total strain was reduced and compression strain was achieved when using LTT filler materials. For an optimal use of the LTT effect in the root of multi-pass welds, the alloying concept must be adapted taking care of dilution.

KEYWORDS:

• Low transformation temperature filler materials
• dilution
• phase transformation
• multi-pass welding
• GMAW
• strain
• synchrotron diffraction
• ADXRD

Acknowledgements

Parts of this research were carried out at the storage ring-based X-ray radiation source PETRA III at DESY. The authors would like to thank DESY for granting beamtime.

Disclosure statement

No potential conflict of interest was reported by the authors.

ORCID

Arne Kromm http://orcid.org/0000-0003-0340-9656

Jens Gibmeier http://orcid.org/0000-0002-5487-8025

Additional information

Funding

Furthermore, the authors would like to especially acknowledge the German Research Foundation (DFG) for funding parts of this work (KA 1807/4-1|GI 376/4-1), Lincoln Electric Europe for the provision of welding consumables as well as EWMAG for support.