Improved mechanical properties of cast Mg alloy welds via texture weakening by differential rotation refill friction stir spot welding

Publikation: Beiträge in ZeitschriftenZeitschriftenaufsätzeForschungbegutachtet

Authors

  • Banglong Fu
  • Junjun Shen
  • Uceu F.H.R. Suhuddin
  • Ting Chen
  • Jorge F. dos Santos
  • Benjamin Klusemann
  • Michael Rethmeier

Cast magnesium alloys welds produced by refill friction stir spot welding (refill FSSW) show low lap shear strength (LSS) and constantly fail in stirred zone (SZ) shear mode. The cause is most probably related to the heavily textured microstructure. Here, to re-engineer the resulting microstructure, we propose a novel process variant, the differential rotation refill FSSW (DR-refill FSSW). DR-refill FSSW stimulates discontinuous dynamic recrystallization and produces a bimodal microstructure with weakened texture. Therefore, the deformation incompatibility between SZ and thermal-mechanically affected zone is avoided. The welds have 50% higher LSS than that of standard refill FSSW welds, and fail in a different failure mode, i.e., SZ pull-out mode. DR-refill FSSW provides a new and effective strategy for improving the performance of spot welds based on microstructural engineering.

OriginalspracheEnglisch
Aufsatznummer114113
ZeitschriftScripta Materialia
Jahrgang203
Anzahl der Seiten6
ISSN1359-6462
DOIs
PublikationsstatusErschienen - 01.10.2021

Bibliographische Notiz

The authors are grateful to Prof. Dr. Norbert Hort at Helmholtz-Zentrum Hereon (HEREON) for providing the Mg alloy ingots. We acknowledge Deutsches Elektronen-Synchrotron DESY (Hamburg, Germany), a member of the Helmholtz Association HGF, for the provision of experimental facilities. Parts of the research were carried out at the High Energy Materials Science (HEMS) of HEREON and we would like to thank Dr. Xiaohua Zhou for assistance in using P07B beamline. We would also like to acknowledge to Dr. Sangbong Yi for training on SABO software. Banglong Fu gratefully acknowledges funding by China Scholarship Council (grant no. 201506220158 ).

DOI