Scholarlink

Abstract <p>To address metallurgical defects, including porosity and residual tensile stress in laser-welded AZ31B magnesium alloy joints, this study employed ultrasonic impact treatment (UIT) using an orthogonal experimental design. Research has demonstrated that UIT generates continuous grooves at the base metal/weld metal interface while producing a smooth transition geometry at the weld toe. Concurrently, this treatment disrupts the original microstructure and crystalline arrangement of the welded surface. Plastic deformation via mechanical impacts induces grain fragmentation at the weld toe, resulting in a more homogeneous and refined grain structure. Consequently, hardness increased by 4.8% in the weld seam and 21.7% at the weld toe. This treatment induced localized compaction of the weld seam surface, significantly enhancing wear resistance and strengthening the fracture-prone weld toe region. Following parameter optimization, sample no. 6 exhibited 2.9% higher ultimate tensile strength and 12.9% greater fracture elongation. Critically, the process transformed residual tensile stresses within the joint into compressive residual stresses, establishing a measurable residual compressive stress layer at the surface.</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

Effect of Ultrasonic Impact Treatment (UIT) on the Microstructure Control and Mechanical Properties of AZ31B Magnesium Alloy Laser Welded Joints

  • 期刊论文

  • 发表日期：

    2025年12月1日

查看全文
  • Yu-lang Xu,
  • Jing-fu Song,
  • Gai Zhao,
  • Xian-rui Zhao,
  • Jing-yong Li,
  • Wu-jia Yin,
  • Deng-guang Xiao

摘要

Abstract

To address metallurgical defects, including porosity and residual tensile stress in laser-welded AZ31B magnesium alloy joints, this study employed ultrasonic impact treatment (UIT) using an orthogonal experimental design. Research has demonstrated that UIT generates continuous grooves at the base metal/weld metal interface while producing a smooth transition geometry at the weld toe. Concurrently, this treatment disrupts the original microstructure and crystalline arrangement of the welded surface. Plastic deformation via mechanical impacts induces grain fragmentation at the weld toe, resulting in a more homogeneous and refined grain structure. Consequently, hardness increased by 4.8% in the weld seam and 21.7% at the weld toe. This treatment induced localized compaction of the weld seam surface, significantly enhancing wear resistance and strengthening the fracture-prone weld toe region. Following parameter optimization, sample no. 6 exhibited 2.9% higher ultimate tensile strength and 12.9% greater fracture elongation. Critically, the process transformed residual tensile stresses within the joint into compressive residual stresses, establishing a measurable residual compressive stress layer at the surface.