Professor Yang obtained his bachelor’s degree from Peking University in 2001, master’s degree from Hong Kong University of Science and Technology in 2003, and PhD degree from Princeton University in 2007. He is now affiliated with several departments in College of Engineering at City University of Hong Kong, and his current research interest includes nanomechanics, design of advanced bulk alloys (e.g., bulk metallic glasses, high entropy alloys) and low dimensional alloys/ceramics (e.g., nanosheets, nanowires, nanoparticles), materials informatics, nano-manufacturing and additive manufacturing (e.g., binder jet 3D printing). His work has been published in multi-disciplinary journals and leading journals in materials, such as Nature, Nature Materials, Nature Communications, Science Advances, PNAS, Advanced Materials, Materials Today, Nano Letters and etc.
High entropy alloys have been recently attracted tremendous research interest worldwide because of their excellent mechanical, chemical and physical properties. In this talk, I would like to discuss our recent work that aims to address some fundamental questions in this field, such as entropic design of alloys and lattice distortion. Through extensive experiments and simulations, we are able to show that it is possible to develop multi-functional high entropy alloys by carefully mixing elements of distinct sizes, which could exhibit a combination of unique mechanical/physical properties, such as superb strength, excellent elastic strain limit, ultralow mechanical hysteresis, remarkable elinvar effect, superior plasticity and many others. At the fundamental level, we found that the multi-functionality of these high order alloys could be attributed to not only chemical fluctuations, but also the presence of heterogeneous lattice strains, both of which however are lacking in conventional alloys.