2-4. Real-time studies of the dynamics of advanced materials processing using synchrotron X-rays
Jiawei Mi
Department of Engineering, University of Hull, Hull, HU6 7RX, UK.
Abstract: Since the 1990s, over a hundred of the 3rd generation Synchrotron X-ray facilities have been built around the world for generating extreme bright X-ray beams to probe materials at multi-length scale (from atomic to metres) and multi-time scale (from picosecond to days). Many of those synchrotron sources have also built dedicated beamlines for studying materials in all type of environmental conditions, for example, for temperature from cryogenic to a few thousand degree centigrade, for pressure from high vacuum to a few hundred of Gigapascal, for mechanical load from static to high impact, etc. These capabilities make it possible for materials scientists to be able to study many dynamic phenomena in materials syntheses and processing that are impossible before, opening a new era for real-time and in-situ studies of materials syntheses and processing, accelerating greatly thediscovery of new materials and the optimisation of materials syntheses.
In this paper, I present the recent findings from our research, including (1) the dynamics of ultrasound processing of metallic alloys, and (2) the dynamics of magnetic field processing of metallic alloys during the solidification processes. We have used ultrafast synchrotron X-ray imaging (upto 271,000 frames per second) to reveal how ultrasonic bubbles oscillate and implode, and how they interact with the crystalline phases during solidification. We also have used ultrafast tomography technique to show how magnetic pulses affect the growing dendritic and intermetallic phases during solidification processes. The research provides unambiguous real-time evidence and quantitative understanding on how ultrasound and magnetic pulses enhance the fragmentation of crystalline phases, laying a solid foundation for further optimising and upscaling those processing techniques for different materials systems.
Professor of Materials at the Department of Engineering, University of Hull UK. His expertise is mainly on the design and development of advanced metallic alloys, composites and the related novel solidification and spray deposition technologies. He obtained his BEng in Materials Engineering in 1984 from the Northwestern Polytechnical University, Xi’an China, MEng in Aerospace Materials in 1989 from Beijing Institute of Aeronautical Materials (BIAM), and PhD in Metallurgy in 2002 from the University of Birmingham UK. He was a research engineer, senior engineer and then Departmental Director at BIAM before moved to the UK in 1998. He was a Research Fellow at the Department of Materials, University of Oxford from 2002 to 2010. He was awarded a Royal Society Industry Fellowship from 2012 to 2016. His recent research has been focusing on using synchrotron X-ray and neutron beam to study in-situ and in real-time the dynamics of atomic, nano and microstructural evolutions of structural and functional materials processed by ultrasound and electromagnetic fields. He has published >130 research papers, wrote and edited the first technical book on “Solidification Processing of Metallic Alloys under External Fields” which has attracted over 3000 paid downloads since published in Oct 2018.
Email: j.mi@hull.ac.uk