Microstructure and mechanical properties of high-strength steel welding consumables with a minimum yield strength of 1100 MPa

Research output: Contribution to journalArticleResearchpeer-review

Authors

External Organisational units

  • voestalpine Stahl Linz GmbH
  • voestalpine Böhler Welding Austria GmbH

Abstract

Welded high-strength steel components have great potential for use in lightweight constructions or highly loaded structures. Welding of steels with a yield strength of more than 1100 MPa is particularly challenging because of the toughness requirements for the weld metal. Currently, a new generation of welding consumables with a minimum yield strength of 1100 MPa has been developed. Based on electron backscatter diffraction and atom probe tomography, a concept for toughening and strengthening of all-weld metal samples was deployed. Starting from a martensitic all-weld metal sample with an approximate yield strength of 1000 MPa, a reduction in manganese and silicon content resulted in a refined microstructure with a lower prior austenite grain size and effective grain size. Furthermore, a higher average grain boundary misorientation was measured, which influences the toughness positively. An addition of vanadium caused the formation of vanadium-rich clusters, which increased the strength of the all-weld metal significantly. With a combination of these two mechanisms, it was possible to produce an all-weld metal sample with the required yield strength of more than 1100 MPa and an acceptable toughness.

Details

Original languageEnglish
Pages (from-to)6968-6979
Number of pages12
JournalJournal of materials science
Volume53.2018
Issue numberMay
DOIs
Publication statusPublished - 24 Jan 2018