Yao Hu is a final-year PhD student from Chalmers University of Technology, working in the Division of Microstructure Physics under the supervision of Dr. Magnus Hörnqvist Colliander and Dr. Sheng Guo.
His research focuses on investigating local structural effects in refractory high-entropy alloys (RHEAs) using synchrotron and neutron total scattering techniques.
Yao’s project can help in understanding the structure-property relationships at atomic level, and offering a basis for the design of next-generation high-temperature materials through local structure engineering.
The material Yao has been working on, RHEAs, is a novel class of alloys composed of multiple high-melting-point metallic elements, known for their exceptional mechanical properties at high temperatures over ~1000 °C. These alloys are promising candidates for next-generation aerospace applications, potentially surpassing the performance limits of current Ni-based superalloys in critical components like aeroengine turbines. A key factor contributing to the strength of RHEAs is local lattice distortion (LLD), arises from atomic size mismatches among constituent elements. LLDs have been shown to influence dislocation movement and solid solution strengthening, making them critical to mechanical performance. However, precise quantification of LLDs remains challenging due to difficulties in obtaining reliable and consistent data.
To address this challenge, Yao uses total scattering combined with pair distribution function (PDF) analysis, which is a powerful technique that simultaneously captures both long-range order (via Bragg diffraction) and local disorder (through diffuse scattering) in materials. This approach allows him to directly characterise local structural effects such as LLDs at atomic resolution. His aim is to understand the local structure of RHEAs, quantify the magnitude of LLDs and uncover their structural origins.
“Working in neutron scattering is a special experience—it’s not something you can easily access in a lab, but it offers unique capabilities to probe materials in ways no other technique can,” Yao explains. “Using neutrons also means a lot of travelling, which has given me the opportunity to regularly interact and collaborate with scientists from across Europe. That’s been an incredible way to learn, grow, and broaden my perspective. I think that’s the most exciting part of the work.”
Being a PhD student of the SwedNess graduate school has expanded even more opportunities through specialised courses, hands-on training, and visits to some of the world-leading neutron facilities. “These experiences have been invaluable not just for my professional development, but also for my personal growth”, says Yao.
Contact
More information: https://www.chalmers.se/en/persons/yaoh/
Email: yao.hu@chalmers.se
LinkedIn: Yao Hu