Wang Haojie, Chen Zhongfeng, Xiong Lianghua, Zhang Shuya, Yin Xiaoyu, Wang Feixiang, Zhang Haipeng, Xie Honglan, He Lin, Du Dafan, Dong Anping, Xiao Tiqiao, Sun Baode
Shanghai Key Lab of Advanced High-Temperature Materials and Precision Forming, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China.
Shanghai Synchrotron Radiation Facility, Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201204, People's Republic of China.
Rev Sci Instrum. 2024 Jul 1;95(7). doi: 10.1063/5.0194938.
Counter-gravity casting (CGC) aims to eliminate turbulent melt flow and defect formation during filling and subsequent solidification by pushing high-temperature melt into the mold cavity against gravity with regulated pressure. However, limited by the opaqueness of molten metals and the complexity of the CGC apparatus, it is extremely difficult to directly quantify the high-velocity mold filling and pressurized solidification in real-time. Here, we report the design and characterization of a CGC system capable of in situ monitoring of mold filling and subsequent solidification processes in the synchrotron beamlines by deploying a high-energy, high-speed synchrotron x-ray imaging technique. The high-velocity melt flow and dendrite growth during pressurized solidification have been quantified for systematical process parameter analysis by investigating time-resolved x-ray images of an exemplary Al-Cu alloy. The high-speed imaging results demonstrate that the in situ CGC system provides a useful way to better understand the fundamentals of mold filling, pressurized solidification, and experimental inputs for high-fidelity modeling in scientific and industrial applications.
反重力铸造（CGC）旨在通过在规定压力下将高温熔体逆着重力推向模具型腔，消除充型过程中熔体的紊流流动以及随后凝固过程中的缺陷形成。然而，受熔融金属不透明性和CGC设备复杂性的限制，实时直接量化高速模具充型和加压凝固极为困难。在此，我们报告了一种CGC系统的设计与特性，该系统通过部署高能、高速同步加速器X射线成像技术，能够在同步加速器光束线中对模具充型和随后的凝固过程进行原位监测。通过研究一种典型Al-Cu合金的时间分辨X射线图像，对加压凝固过程中的高速熔体流动和枝晶生长进行了量化，以进行系统的工艺参数分析。高速成像结果表明，原位CGC系统为更好地理解模具充型、加压凝固的基本原理以及科学和工业应用中高保真建模的实验输入提供了一种有用的方法。
