三轴滚动对反应器压力容器的微观结构和安装特征的影响
Wei Zhu1,2, Hua Li3, Decheng Wang4
1China Productivity Center for Machinery, China Academy of Machinery Science and Technology, Beijing, 100044, China.
Scientific reports
|September 6, 2024
概括
反应器压力容器 (RPV) 螺栓的三轴滚动细化了线根微观结构,产生了超细粒和强的纹理. 这导致安装过程中剩余延长率减少6%,提高了RPV杆的性能.
科学领域:
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
- 核工程 核工程是指核工程.
背景情况:
- 反应堆压力容器 (RPV) 螺栓对于在极端条件下密封核反应堆至关重要.
- RPV线的完整性直接影响了反应堆的安全性和运行效率.
研究的目的:
- 为了研究三轴滚动对RPV杆外部线程的微观结构和纹理的影响.
- 评估三轴滚动对RPV杆安装特征的影响.
主要方法:
- 有限元素分析与粘性塑料自相一致的模拟相结合,用于纹理演变的预测.
- 扫描电子显微镜和电子背散射衍射用于微观结构的特征.
- 安装和预紧固测试,以评估杆的性能.
主要成果:
- 三轴滚动诱导了动态再结晶,形成了超细炼的酸盐粒和高角粒边界 (47%) 在线程根部.
- 在线根材料中观察到强烈的{111} <110>和{111} <112>纹理.
- 与相同负载下转部件相比,制RPV杆部件的残余延伸减少了6%.
结论:
- 三轴滚动在RPV线根中创建了一个梯度微结构,优化了它们的特性.
- 精致的微观结构和纹理增强了杆安装特性,提高了密封性能和可靠性.
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