TY - JOUR

T1 - Improved mechanical properties of cast Mg alloy welds via texture weakening by differential rotation refill friction stir spot welding

AU - Fu, Banglong

AU - Shen, Junjun

AU - Suhuddin, Uceu F.H.R.

AU - Chen, Ting

AU - dos Santos, Jorge F.

AU - Klusemann, Benjamin

AU - Rethmeier, Michael

PY - 2021/10/1

Y1 - 2021/10/1

N2 - 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.

AB - 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.

KW - EBSD

KW - Magnesium alloy

KW - Plastic deformation

KW - Refill friction stir spot welding

KW - Texture

KW - Engineering

UR - http://www.scopus.com/inward/record.url?scp=85109440699&partnerID=8YFLogxK

UR - https://www.mendeley.com/catalogue/53033d88-4cf9-34a1-ade0-63b4c2741a50/

U2 - 10.1016/j.scriptamat.2021.114113

DO - 10.1016/j.scriptamat.2021.114113

M3 - Journal articles

AN - SCOPUS:85109440699

VL - 203

JO - Scripta Materialia

JF - Scripta Materialia

SN - 1359-6462

M1 - 114113

ER -