研究老化温度的热压缩行为和微观结构的新Ni-Cr-Co-基于超级合金的研究
Hualin Cai1, Zhixuan Ma1, Jiayi Zhang1
1School of Materials Science and Engineering, Jiangxi University of Science and Technology, Ganzhou 341000, China.
Materials (Basel, Switzerland)
|July 27, 2024
概括
在950°C时老化的基超级合金增强了高温强度. 这种处理优化了强化阶段,通过抑制排位运动和动态再结晶来改善机械性能和微硬度.
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.
- 航空航天工程 航空航天工程
背景情况:
- 基于的超级合金由于其高温强度,对航空航天应用至关重要.
- 优化加固阶段对于提高这些合金的性能至关重要.
研究的目的:
- 为了研究基于的新型超级合金的热变形行为和微观结构演变.
- 为了确定最佳的老化处理,以改善高温机械性能.
主要方法:
- 在650°C,750°C,850°C和950°C的温度下,对超级合金进行了一系列老化处理,持续8小时.
- 进行了热压缩测试,以评估机械性能和微观结构变化.
- 在变形之前和之后进行了微硬度和应力测量.
主要成果:
- 在950°C老化的样本在热压缩后表现出峰值应力 (~323 MPa) 和最高微硬度 (~315 HV).
- 经过950°C的老化,该样本显示出异形的纤维状颗粒,与其他样本不同,具有同otropic 方向.
- 在850°C和950°C的老化样本中,~20nm γ'阶段的沉抑制了脱位运动和动态再结晶.
结论:
- 在950°C时老化基超级合金显著改善了高温机械性能.
- 精制的γ'沉物通过阻碍脱位运动,在加强合金方面发挥着至关重要的作用.
- 这项研究提供了对优化基于的超级合金,以满足航空航天应用的需求的见解.
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