在Fe-Cr合金中核增长与脊柱分解:通过原子探测器断层和小角度中子散射进行实验验证
Sudip Kumar Sarkar1,2, Debes Ray3, Debasis Sen2,3
1Materials Science Division, Bhabha Atomic Research Centre, Mumbai 400085, India.
概括
这项研究区分了Fe-Cr合金中的旋点分解 (SD) 与核化增长 (NG) 阶段分离,使用原子探头断层扫描和SANS. 新的SANS配置功能可靠地区分这些关键相位分离机制.
科学领域:
- 材料科学 材料科学 材料科学
- 物理金学 物理金学
- 阶段转换 阶段转换 阶段转换
背景情况:
- 区分旋点分解 (SD) 和核化生长 (NG) 对于理解相位分离至关重要.
- Fe-Cr系统是研究这些现象的模型系统,与不钢和其他合金有关.
- 以前的方法很难在这个系统中明确区分SD和NG.
研究的目的:
- 批判性地检查并建立一个框架来区分SD和NG在热老化Fe-Cr合金中的区别.
- 识别原子探头断层扫描 (APT) 和小角度中子散射 (SANS) 数据中的关键特征,这些数据独特地描述了每个相位分离模式.
- 提供一种可靠的方法来确定Fe-Cr合金中的操作相分离机制.
主要方法:
- 原子探头断层扫描 (APT) 用于分析化学波动和接口特征.
- 小角度中子散射 (SANS) 提供了相位分离动力学的补充数据.
- 采用了射线分布函数分析 (APT) 和SANS配置特征分析 (FWHM,动态缩放指数 γ).
主要成果:
- APT成功地确定了化学波动和接口度的差异 (SD的扩散,NG的).
- SANS相关性峰值最初无法区分SD和NG.
- 确定了关键的SANS配置特征,包括FWHM的时间演变和动态缩放指数 (SD的γ=6,NG的γ=4),以明确区分模式.
结论:
- 已经建立了一个结合APT和SANS的强大框架,以区分Fe-Cr合金中的SD和NG.
- 特定的SANS配置特征提供了确定阶段分离机制的最终标记.
- 这项工作为了解金属合金中的相隔动力学提供了关键的进步.
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