Sedimentation Process and Phase Transition of Solids Under High Gravity

Abstract:

The recent progress and future prospects for ultra-centrifugal sedimentation in solids are described, mainly involving equipment, miscible systems and compounds. Almost 90% ultracentrifugation experiments were performed on the 1st and 2nd high-temperature ultracentrifuge which is typically operated at temperatures below 500 °C under the maximum centrifugal acceleration up to 10⁶ g. The strong gravitational and temperature fields induce atomic-scale graded structure, grain growth and refinement, and voids accumulation caused by the atomic sedimentation in miscible systems. New structures, properties and substances are produced in some compounds. A new cantilever high-temperature ultracentrifuge with a test temperature up to 1200 °C is under construction at Zhejiang University, making it possible to simulate the composition, microstructure and property evolution of superalloys in the operating environment of aircraft engines.