Scholarlink

<p>Grain boundary character plays a critical role in corrosion processes, particularly in aggressive or acidic environments where preferential dissolution and oxide formation can localize at microstructural features. Prior studies have shown the effect of different crystallographic grain orientations on oxygen adsorption, with Fe (100) surfaces favoring more stable oxide formation than Fe (110); however, the effect of grain boundary character remains largely unaddressed in the literature. This study investigates the influence of grain boundary misorientation on oxide deposition behavior in pipeline steel. Using a combination of EBSD and surface analytical techniques (SEM, XPS, and surface profilometry), the distribution, thickness, and composition of corrosion-induced oxides were correlated with local grain boundary misorientations. The results revealed that high-angle grain boundaries exhibit significantly more oxide accumulation, with thicker corrosion product layers observed with increasing misorientation angles. DFT calculations indicate that high-angle grain boundaries (HAGBs) have stronger oxygen adsorption and promote dissociative adsorption, which supports the experimental observation of thicker and more continuous oxide layers forming along HAGBs. Furthermore, XPS results identified Fe<sub>2</sub>O<sub>3</sub> as the dominant product after corrosion. These results demonstrate a clear relationship between grain boundary misorientation and oxide formation behavior in acidic environments.</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

Experimental and Density Functional Theory Investigation of Grain Boundary Character on Oxide Layer Growth in Pipeline Steel under Acidic Environment

  • 期刊论文

  • 发表日期：

    2025年9月2日

查看全文
  • Meekness Nnoka,
  • Omar Faye,
  • Tonye Alaso Jack,
  • Jerzy Szpunar

摘要

Grain boundary character plays a critical role in corrosion processes, particularly in aggressive or acidic environments where preferential dissolution and oxide formation can localize at microstructural features. Prior studies have shown the effect of different crystallographic grain orientations on oxygen adsorption, with Fe (100) surfaces favoring more stable oxide formation than Fe (110); however, the effect of grain boundary character remains largely unaddressed in the literature. This study investigates the influence of grain boundary misorientation on oxide deposition behavior in pipeline steel. Using a combination of EBSD and surface analytical techniques (SEM, XPS, and surface profilometry), the distribution, thickness, and composition of corrosion-induced oxides were correlated with local grain boundary misorientations. The results revealed that high-angle grain boundaries exhibit significantly more oxide accumulation, with thicker corrosion product layers observed with increasing misorientation angles. DFT calculations indicate that high-angle grain boundaries (HAGBs) have stronger oxygen adsorption and promote dissociative adsorption, which supports the experimental observation of thicker and more continuous oxide layers forming along HAGBs. Furthermore, XPS results identified Fe2O3 as the dominant product after corrosion. These results demonstrate a clear relationship between grain boundary misorientation and oxide formation behavior in acidic environments.