Scholarlink

<p>The fracture behaviors of Q500 steel under different hydrogen charging durations were investigated using internal friction testing, slow strain rate tensile (SSRT) testing, electrochemical hydrogen charging, and hydrogen microprinting. Results show that the experimental steel has a bainitic microstructure. After hydrogen charging, only a small number of hydrogen atoms are detected within the grains, with the majority accumulating at prior austenite grain boundaries, interfaces between massive and lath bainitic ferrite, lath packet boundaries, lath boundaries, and martensite-austenite (M/A) islands. Among the identified internal friction peaks—including the hydrogen-dislocation interaction peak (P1), carbon B peak (P3), carbon Snoek-Köster peak (P4), and grain boundary peak (P5)—their activation energies decrease gradually as the hydrogen charging duration increases from 3 to 6&#xa0;h. The fracture mode of Q500 steel is controlled by local hydrogen concentration: in the central region of the fracture surface with lower hydrogen levels, the fracture mode is fine microporosity coalescence driven by hydrogen-enhanced local plastic deformation and the hydrogen-promoted strain-induced vacancy mechanism; in the edge region with higher hydrogen concentration, the fracture mode transitions to cleavage fracture, primarily caused by hydrogen-induced decohesion with a secondary effect of hydrogen-promoted local plastic deformation.</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

A Study on the Fracture Mechanism of Q500 Steel under Different Hydrogen Charging Times

  • 期刊论文

  • 发表日期：

    2025年10月30日

查看全文
  • Cui Chen,
  • Yue Pan,
  • Weijuan Li,
  • Dazheng Zhang,
  • Qihang Pang,
  • Tingfeng Xu,
  • Zhiyi Ma

摘要

The fracture behaviors of Q500 steel under different hydrogen charging durations were investigated using internal friction testing, slow strain rate tensile (SSRT) testing, electrochemical hydrogen charging, and hydrogen microprinting. Results show that the experimental steel has a bainitic microstructure. After hydrogen charging, only a small number of hydrogen atoms are detected within the grains, with the majority accumulating at prior austenite grain boundaries, interfaces between massive and lath bainitic ferrite, lath packet boundaries, lath boundaries, and martensite-austenite (M/A) islands. Among the identified internal friction peaks—including the hydrogen-dislocation interaction peak (P1), carbon B peak (P3), carbon Snoek-Köster peak (P4), and grain boundary peak (P5)—their activation energies decrease gradually as the hydrogen charging duration increases from 3 to 6 h. The fracture mode of Q500 steel is controlled by local hydrogen concentration: in the central region of the fracture surface with lower hydrogen levels, the fracture mode is fine microporosity coalescence driven by hydrogen-enhanced local plastic deformation and the hydrogen-promoted strain-induced vacancy mechanism; in the edge region with higher hydrogen concentration, the fracture mode transitions to cleavage fracture, primarily caused by hydrogen-induced decohesion with a secondary effect of hydrogen-promoted local plastic deformation.