Welding in the World

, Volume 62, Issue 5, pp 985–995 | Cite as

On the design of fillet welds made of ultra-high-strength steel

  • Timo BjörkEmail author
  • Antti Ahola
  • Niko Tuominen
Research Paper


Current static design approaches for fillet arc welds made of high- or ultra-high-strength steel (UHSS) do not differ from the design of welds made of conventional steels. However, important issues such as potential softening in heat-affected zone (HAZ), strength at fusion lines, optimal reinforcement geometry, load capacity changes due to local bending moment, and the effect of post-weld treatments on the joint strength require careful consideration in order to ensure optimum performance from these steels. This paper reprises results of previous research works and recent findings and summarizes key aspects of weld design specific to UHSS welds.


Static strength Welded joint Fillet welds Throat thickness Ultra-high-strength steels 



The authors wish to thank SSAB, DIMECC Ltd., and the Finnish Funding Agency for Innovation (TEKES) for funding the BSA (Breakthrough Steels and Applications) program that enabled this research work to be completed. Additionally, the authors express their gratitude to the IT Center for Science (CSC) for providing the licensing of software.


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Copyright information

© International Institute of Welding 2018

Authors and Affiliations

  1. 1.Laboratory of Steel StructuresLappeenranta University of Technology (LUT)LappeenrantaFinland

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