用于在TEM中实际测量温度的光谱测量
D Keith Coffman1, Khalid Hattar2, Jian Luo3
1Department of Materials Science & Engineering, University of Illinois Urbana-Champaign, Champaign, IL 61801, USA.
概括
这项研究为光谱测火法校准和在电子显微镜中的使用提供了实用指南. 它可以在材料研究中准确,无接触的微尺度温度测量超过600°C.
科学领域:
- 材料科学 材料科学 材料科学
- 光学物理学的光学物理学
- 显微镜的使用方法
背景情况:
- 准确的微尺度温度测量对于超高温度的现场电子显微镜至关重要.
- 光学测 pyrometry 提供了一个无接触的解决方案,但由于发射率和传输效应,需要仔细校准.
研究的目的:
- 介绍一本用于校准和利用光谱测量系统进行微尺度温度测定的实用指南.
- 为了证明系统与传输电子显微镜的集成,用于先进的材料分析.
主要方法:
- 使用连接到传输电子显微镜的Czerny-Turner光谱仪对光谱测量系统进行校准.
- 使用热电偶或商用加热样本持有器进行系统校准.
- 在大约600°C以上的温度下测量任意样本.
主要成果:
- 在温度测量中达到2%的准确性.
- 证明了次秒时间分辨率和次凯尔文温度分辨率的潜力.
- 成功地整合了高 pyrometry 和基于衍射的应变测量和现场视频烧结观测.
结论:
- 开发的光谱测量系统为高温电子显微镜中无接触温度测量提供了可靠的方法.
- 这种技术增强了对材料在微观尺度上的热性质和动态过程的研究.
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