抗,Al2O3形成的奥氏体不钢
Y Yamamoto1, M P Brady, Z P Lu
1Materials Science and Technology Division Oak Ridge National Laboratory Oak Ridge, TN 37831-6115, USA.
概括
新的奥氏体不钢提供了增强的高温性能. 这些具有成本效益的合金为能源应用提供了卓越的爬行强度和抗氧化能力.
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.
- 高温合金是一种高温合金.
背景情况:
- 开发用于高温应用的先进材料对于提高能量转换效率和元件寿命至关重要.
- 现有的高强度钢通常在激烈的氧化环境和高工作温度下面临限制.
- 奥氏体不钢由于其机械性能是可取的,但需要在极端条件下进行增强.
研究的目的:
- 开发一种新的经济高效,高爬强度的奥氏体不钢家族,能够形成保护性 (Al2O3) .
- 为了使要求高的能量转换系统中结构部件的运行温度更高.
- 研究特定合金元素对抗爬行和氧化行为的影响.
主要方法:
- 基于Fe-20Ni-14Cr-2.5Al (重量百分比) 组成的合金设计.
- 通过碳化物 (NbC) 的纳米分散实现了强化.
- 消除和以促进Al2O3的状形成,并稳定奥氏体矩阵.
- 在各种高温条件下测试爬行破裂寿命和抗氧化性.
主要成果:
- 在750°C和100MPa的空气中,已证明的爬行破裂寿命超过2000小时.
- 与以前的合金相比,实现了与含量减少的保护性Al2O3形.
- 在空气中与10%的水蒸气一起,在650°C和800°C时表现出抗氧化能力.
- 证实了奥氏体矩阵结构的稳定.
结论:
- 开发的廉价,Al2O3形成的奥氏体不钢具有出色的爬行强度和抗氧化能力.
- 这些合金具有显著的潜力,可以提高能源转换系统中的结构部件的操作温度.
- 优化合金成分,特别是减少Al和消除Ti/V,是实现卓越高温性能的关键.
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