Scholarlink

<p>This paper discusses the grain evolution characteristics of friction stir welding (FSW) of a novel Al–Cu–Mn–Er–Zr alloy at different welding speeds. It focuses on the dynamic recrystallization (DRX) behavior of the joint and the evolution of precipitated phases in each region at a welding speed of 200&#xa0;mm/min. Furthermore, the study investigated the strengthening mechanism of the weld joint, which was augmented by an aging treatment subsequent to the welding process. The results indicate that the grain size in the weld nugget zone (WNZ) is significantly refined, with the average grain size gradually decreasing as welding speed increases. As the distance from the WNZ decreases, discontinuous recrystallization (DDRX), continuous recrystallization (CDRX), and geometric recrystallization (GDRX) occur sequentially, thereby promoting grain refinement. The sequential evolution of the predominant precipitated phases can be delineated as follows: initially, a fine, high-density <i>θ</i>′ phase is observed within the Base Metal (BM); this transitions to larger, high-density <i>θ</i>′ phases within the heat-affected zone (HAZ). Subsequently, the thermo-mechanically affected zone (TMAZ) exhibits a heterogeneous distribution of <i>θ</i>′ phases, culminating in the formation of equilibrium <i>θ</i> phases within the WNZ. The Er elements inhibit the growth of the <i>θ</i>′ phase by aggregating on it, demonstrating a synergistic evolution. Analysis of the strengthening mechanisms reveals that the key factors affecting the yield strength (YS) of the joint are the density and size of the precipitated phases. These findings provide a new perspective for the study of Er microalloying in Al–Cu alloys.</p> Graphical abstract <p></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

Microstructural evolution and synergistic effect of Er and θ′ phases of a novel Al–Cu–Mn–Er–Zr alloy during friction stir welding

  • 期刊论文

  • 发表日期：

    2025年2月25日

查看全文
  • Hongxing Yang,
  • Dongwei Zhang,
  • Li Rong,
  • Chenxi Ma,
  • Jiongshen Chen,
  • Wu Wei,
  • Hui Huang,
  • Xiaocheng Shi,
  • Shengping Wen,
  • Kunyuan Gao,
  • Xiaolan Wu,
  • Zezhong Wang

摘要

This paper discusses the grain evolution characteristics of friction stir welding (FSW) of a novel Al–Cu–Mn–Er–Zr alloy at different welding speeds. It focuses on the dynamic recrystallization (DRX) behavior of the joint and the evolution of precipitated phases in each region at a welding speed of 200 mm/min. Furthermore, the study investigated the strengthening mechanism of the weld joint, which was augmented by an aging treatment subsequent to the welding process. The results indicate that the grain size in the weld nugget zone (WNZ) is significantly refined, with the average grain size gradually decreasing as welding speed increases. As the distance from the WNZ decreases, discontinuous recrystallization (DDRX), continuous recrystallization (CDRX), and geometric recrystallization (GDRX) occur sequentially, thereby promoting grain refinement. The sequential evolution of the predominant precipitated phases can be delineated as follows: initially, a fine, high-density θ′ phase is observed within the Base Metal (BM); this transitions to larger, high-density θ′ phases within the heat-affected zone (HAZ). Subsequently, the thermo-mechanically affected zone (TMAZ) exhibits a heterogeneous distribution of θ′ phases, culminating in the formation of equilibrium θ phases within the WNZ. The Er elements inhibit the growth of the θ′ phase by aggregating on it, demonstrating a synergistic evolution. Analysis of the strengthening mechanisms reveals that the key factors affecting the yield strength (YS) of the joint are the density and size of the precipitated phases. These findings provide a new perspective for the study of Er microalloying in Al–Cu alloys.

Graphical abstract