Scholarlink

<p>This paper investigates the Fatigue Crack Growth (FCG) characteristics of 2017&#xa0;A-T451 aluminum alloy sheets joined via Friction Stir Welding (FSW). To determine the mechanical sensitivity of the weld’s internal architecture, Compact Tension (CT-50) specimens were extracted with notches specifically aligned within the distinct thermomechanical zones. Experimental results were utilized to calculate Paris law parameters and to model the extent of plastic deformation using Irwin’s approach. The findings demonstrate that while the base material retains superior crack-opening resistance, the FSW process induces significant variations in fatigue kinetics. The fatigue analysis reveals that the Nugget Zone (NZ) exhibits a localized reduction in cyclic plasticity. Rather than a purely brittle response, this behavior is driven by the dynamic recrystallization process which results in ultra-fine equiaxed grains. These grains, while increasing local hardness, limit the volume available for dislocation multiplication and storage, thereby constraining the plastic zone development and leading to the observed low-ductility fracture features. Conversely, the TMAZ displayed the lowest propagation rates. These results provide critical insights into the localized damage mechanisms of FSW joints, establishing a direct correlation between microhardness gradients, microstructural evolution, and the plastic zone radius at the crack tip.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Local fatigue crack growth behaviour of friction stir welded joint of 2017 A-T451 aluminum alloy

  • 期刊论文

  • 发表日期：

    2026年6月18日

查看全文
  • Ibrahim Ayad,
  • Karim BENSLIMANE Sidi Mohammed,
  • Oussama Mimouni,
  • Mohammed Hadj Meliani,
  • Benameur Hamoudi,
  • Nabil Chekroun,
  • Riadh Badji,
  • Larbi Hemmouche

摘要

This paper investigates the Fatigue Crack Growth (FCG) characteristics of 2017 A-T451 aluminum alloy sheets joined via Friction Stir Welding (FSW). To determine the mechanical sensitivity of the weld’s internal architecture, Compact Tension (CT-50) specimens were extracted with notches specifically aligned within the distinct thermomechanical zones. Experimental results were utilized to calculate Paris law parameters and to model the extent of plastic deformation using Irwin’s approach. The findings demonstrate that while the base material retains superior crack-opening resistance, the FSW process induces significant variations in fatigue kinetics. The fatigue analysis reveals that the Nugget Zone (NZ) exhibits a localized reduction in cyclic plasticity. Rather than a purely brittle response, this behavior is driven by the dynamic recrystallization process which results in ultra-fine equiaxed grains. These grains, while increasing local hardness, limit the volume available for dislocation multiplication and storage, thereby constraining the plastic zone development and leading to the observed low-ductility fracture features. Conversely, the TMAZ displayed the lowest propagation rates. These results provide critical insights into the localized damage mechanisms of FSW joints, establishing a direct correlation between microhardness gradients, microstructural evolution, and the plastic zone radius at the crack tip.