由1500t造模拟器造的Ti合金的微观结构演化和疲劳性能
Yoko Yamabe-Mitarai1, Norie Motohashi2, Shuji Kuroda2
1Advanced Materials Science, Graduate School of Frontier Science, The University of Tokyo, 5-1-5, Kashiwanoha, Kashiwa 277-8561, Chiba, Japan.
Materials (Basel, Switzerland)
|April 24, 2025
概括
用热机械加工 (TMP) 处理的大型 TIMETAL 834 样本显示疲劳寿命有所改善. 大样本的缓慢冷却允许微观结构变化,与快速冷却的小样本不同.
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.
- 机械工程 机械工程
背景情况:
- 微结构控制对于提高 (Ti) 合金如Ti-6Al-4V和TIMETAL 834的疲劳寿命至关重要.
- 之前的研究经常使用小样本,导致快速冷却速度与大型发动机组件不同.
研究的目的:
- 使用热力学处理 (TMP) 调查 TIMETAL 834 大样本中的微结构变化.
- 建立一个宏观的理解,将Ti合金的加工,微观结构和疲劳寿命联系起来.
主要方法:
- 使用了大型的 TIMETAL 834 样品 (直径 80 毫米,高度 100 毫米).
- 采用1500的造模拟器在940°C和1000°C下进行造.
- 在 900 °C 和 1000 °C 应用热处理.
主要成果:
- 大型样本表现出双模结构或由于缓慢冷却和扩散而导致α (α) 阶段的全球化.
- 由于快速冷却,小样本保留了变形的微观结构.
- 85%的造在1000°C显著改善了疲劳寿命.
结论:
- 大型组件的缓慢冷却促进了有益的微结构演变 (例如,α阶段全球化).
- 精制的α粒和对齐的α粒c轴有助于改善疲劳寿命.
- 大型Ti合金组件上的TMP有效地提高了疲劳性能.
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