在真空中化过程中扩大奥氏体的稳定性
Stephan Mändl1, Hyemin Oh1, Daniel Hristov1
1Leibniz Institute of Surface Engineering (IOM), Permoserstr. 15, 04318 Leipzig, Germany.
Materials (Basel, Switzerland)
|February 13, 2025
概括
不钢中的膨胀奥氏体在高达350°C时保持稳定. 它在真空化过程中的衰变是热激活的,扩散限制了高温应用.
科学领域:
- 材料科学 材料科学 材料科学
- 金工业是金工业的一个方面.
- 表面工程是什么?表面工程是什么?
背景情况:
- 通过等离子浸泡离子化形成的扩展奥氏体层,为不钢提供了增强的表面性能.
- 对于实际应用来说,研究这些层在后处理化过程中的稳定性至关重要.
研究的目的:
- 在真空化过程中确定不钢 (316Ti,904L,318LN) 中膨胀奥氏体的稳定性.
- 了解扩展奥氏体衰变和扩散的机制和动力学.
主要方法:
- 在现场进行X射线衍射 (XRD),用于监测化过程中的结构变化.
- 飞行时间二次离子质谱 (ToF-SIMS) 用于分析深度概况和CrN沉.
- 用于解释ToF-SIMS数据的集群分析.
主要成果:
- 膨胀奥氏体的衰变是一个热激活的过程,激活能量为1.8 ± 0.3 eV.
- 腐蚀在550°C开始迅速,在450°C以下进展缓慢,在受影响的区域内均发生.
- 扩散使分析复杂化,但被确定为高温 (高达350°C) 操作的限制因素,而不是CrN沉.
结论:
- 膨胀的奥氏体层表现出高达350°C的显著热稳定性.
- 扩散,而不是CrN沉,决定了耐磨扩展奥氏体的操作温度极限.
- 建议进一步使用传输电子显微镜进行详细的微观结构分析.
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