老化的FeNiCoAlTiNb冷形状记忆合金的热循环行为
Li-Wei Tseng1, Wei-Cheng Chen1
1Department of Mechatronics Engineering, National Changhua University of Education, Changhua 50007, Taiwan.
Micromachines
|November 27, 2024
概括
这项研究研究了Fe-Ni-Co-Al合金,揭示了最佳的回火和老化条件会产生2%的可回收应变. 然而,脆粒边界限制了柔性,这表明需要进一步的研究来增强形状记忆特性.
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.
- 形状记忆合金的合金
背景情况:
- 基于Fe-Ni-Co-Al的合金因其显著的可回收应变而闻名.
- 了解微观结构和热循环行为对于优化这些合金至关重要.
研究的目的:
- 为了研究特定FeNiCoAlTiNb合金的微观结构和热循环行为.
- 为了确定最佳的回火和老化条件,以增强形状记忆特性.
主要方法:
- 电子反射散射衍射 (EBSD) 用于纹理和颗粒大小分析.
- 传输电子显微镜 (TEM) 用于沉物的表征.
- 用于相位分析的X射线衍射 (XRD).
- 磁化-温度曲线和三点曲试验用于性能评估.
主要成果:
- 化增加了纹理强度和颗粒大小.
- 在600°C的峰值老化时间为48小时,最大硬度.
- 合金表现出2%的可回收应变,尽管低于理论预测.
- 脆粒边界和β相被确定为限制因素.
结论:
- 对于Fe-Ni-Co-Al合金来说,优化热处理 (和老化) 是非常重要的.
- 脆弱的β阶段的存在和不足的低角粒边界阻碍了实现理论可回收应变.
- 进一步的研究应侧重于减轻谷物边界脆性,以提高柔性和形状记忆性能.
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