Inhibiting weld cracking in high-strength aluminium alloys

Yanan Hu, Shengchuan Wu, Yi Guo, Zhao Shen, Alexander M. Korsunsky, Yukuang Yu, Xu Zhang, Yanan Fu, Zhigang Che, Tiqiao Xiao, Sergio Lozano-Perez, Qingxi Quan, Xiangli Zhong, Xiaoqin Zeng, Guozheng Kang, Philip J. Withers

Research output: Contribution to journalArticlepeer-review

Abstract

Cracking from a fine equiaxed zone (FQZ), often just tens of microns across, plagues the welding of 7000 series aluminum alloys. Using a multiscale correlative methodology, from the millimeter scale to the nanoscale, we shed light on the strengthening mechanisms and the resulting intergranular failure at the FQZ. We show that intergranular AlCuMg phases give rise to cracking by micro-void nucleation and subsequent link-up due to the plastic incompatibility between the hard phases and soft (low precipitate density) grain interiors in the FQZ. To mitigate this, we propose a hybrid welding strategy exploiting laser beam oscillation and a pulsed magnetic field. This achieves a wavy and interrupted FQZ along with a higher precipitate density, thereby considerably increasing tensile strength over conventionally hybrid welded butt joints, and even friction stir welds.
Original languageEnglish
Article number5816
JournalNature Communications
Volume13
Issue number1
DOIs
Publication statusPublished - 3 Oct 2022

Fingerprint

Dive into the research topics of 'Inhibiting weld cracking in high-strength aluminium alloys'. Together they form a unique fingerprint.

Cite this