Scholarlink

<p>In the realm of titanium alloys, achieving a balance between strength and ductility in high-oxygen Grade 4 commercially pure titanium (CP-Ti) remains a critical challenge, primarily due to oxygen-induced embrittlement and limited deformation mechanisms. This study examines the microstructural evolution of Grade 4 CP-Ti subjected to cold rolling. Multi-pass rolling is shown to induce progressive grain refinement, with the microstructure transforming from an initially equiaxed morphology to a highly elongated fibrous structure. A key observation is the apparent geometric dilution of oxygen and iron segregation at grain boundaries (GBs). Analysis indicates that this effect is predominantly governed by the drastic increase in specific grain boundary area, rather than by chemical desegregation. Dislocation slip, primarily accommodated by prismatic &lt; a &gt; and pyramidal &lt; c + a &gt; systems, gives rise to a distinct interaction with the evolving grain boundary network. Although the geometric dilution of embrittling solutes alleviates premature intergranular fracture, the depletion of work-hardening capacity associated with the high dislocation density ultimately constrains ductility. Overall, this work clarifies the competing mechanisms underlying the strength–ductility in high-oxygen CP-Ti and offers theoretical insight for future studies on high-oxygen pure titanium and its 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

Mechanistic insights into the dislocation-grain boundary interaction and geometric dilution effect in high-oxygen Grade 4 titanium during cold rolling

  • 期刊论文

  • 发表日期：

    2026年3月1日

查看全文
  • Sheng Huang,
  • Chao Chen,
  • Jie Li,
  • Haowei Liang,
  • Kun Liu,
  • Jiaxin Yu,
  • Han Xiao

摘要

In the realm of titanium alloys, achieving a balance between strength and ductility in high-oxygen Grade 4 commercially pure titanium (CP-Ti) remains a critical challenge, primarily due to oxygen-induced embrittlement and limited deformation mechanisms. This study examines the microstructural evolution of Grade 4 CP-Ti subjected to cold rolling. Multi-pass rolling is shown to induce progressive grain refinement, with the microstructure transforming from an initially equiaxed morphology to a highly elongated fibrous structure. A key observation is the apparent geometric dilution of oxygen and iron segregation at grain boundaries (GBs). Analysis indicates that this effect is predominantly governed by the drastic increase in specific grain boundary area, rather than by chemical desegregation. Dislocation slip, primarily accommodated by prismatic < a > and pyramidal < c + a > systems, gives rise to a distinct interaction with the evolving grain boundary network. Although the geometric dilution of embrittling solutes alleviates premature intergranular fracture, the depletion of work-hardening capacity associated with the high dislocation density ultimately constrains ductility. Overall, this work clarifies the competing mechanisms underlying the strength–ductility in high-oxygen CP-Ti and offers theoretical insight for future studies on high-oxygen pure titanium and its alloys.

Graphical abstract