Gyuho will leave this Friday to California to start his new position at the Frore Systems. He will work as a material engineer to develop the Micro-electro-mechanical-system (MEMS) device that cools the high performance CPU much faster than the conventional technologies. Best wishes for his success in Silicon Valley!
Shuyang’s first paper is published at Nano Letters! Many congratulations! The paper is now available online [web]. This work discusses the unique pseudoelasticity mechanisms, double lattice and collapse due to the a solid-state bonding and debonding.
Shuyang Xiao, Vladislav Borisov, Guilherme Gorgen-Lesseux, Sarshad Rommel, Gyuho Song, Jessica M. Maita, Mark Aindow, Roser Valentí, Paul Canfield, Seok-Woo Lee, “Pseudoelasticity of SrNi2P2 micropillar via lattice collapse and expansion,” Nano Letters (2021) [Arxiv] [web]
Abstract: The maximum recoverable strain of most crystalline solids is less than 1% because plastic deformation or fracture usually occurs at a small strain. In this work, we show that a SrNi2P2 micropillar exhibits pseudoelasticity with a large maximum recoverable strain of ∼14% under uniaxial compression via unique reversible structural transformation, double lattice collapse–expansion that is repeatable under cyclic loading. Its high yield strength (∼3.8 ± 0.5 GPa) and large maximum recoverable strain bring out the ultrahigh modulus of resilience (∼146 ± 19 MJ/m3), a few orders of magnitude higher than that of most engineering materials. The double lattice collapse–expansion mechanism shows stress–strain behaviors similar to that of conventional shape-memory alloys, such as hysteresis and thermo-mechanical actuation, even though the structural changes involved are completely different. Our work suggests that the discovery of a new class of high-performance ThCr2Si2-structured materials will open new research opportunities in the field of pseudoelasticity.
Gyuho recently received the job offer from the Frore Systems at San Jose, CA, and will work as a materials researcher. Another Silicon Valley engineer after Tyler Flanagan! Good luck for his new adventure!
Tyler will starts his new position at the Evans Analytical Group in CA. Best wishes for his next career!
Tyler passed his PhD Defense! Many Congratulations, Dr. Flanagan!
Tyler recently accepted the job offer from the Evans Analytical Group (EAG) in the middle of Silicon Valley at California, where I spent my first five years in US. I wish he continues to make a great success in a new place. Congratulations! Yeah!
Seok-Woo gave two invited talks. The title of talk was “Superelasticity of ThCr2Si2-structured intermetallic compounds: Making and Breaking Bonds“. These talks summarized our research on superplasticity of ThCr2Si2-structure intermetallic compounds for the past five years at UConn.
One invited talk was given at Korea Institute of Industrial Technology on August 11, and the other was given as the Department Seminar in the Department of Materials Science and Engineering at Korea University on August 18,
Kyle Wade joins our research group! Welcome! Kyle is going to work on the wire-arc additive manufacturing, which is supported by US Army Research Laboratory. He is going to pursue the master degree (plan A).
Seok-Woo receives the DOE-BES fund ($400,000) for the next three years! Seok-Woo’s group will work on the effects of sample dimension on tensile ductility of single crystalline niobium, tantalum, and tungsten at cryogenic temperatures using in-situ cryogenic nano mechanical testing. This work will also use the advanced computer simulations of dislocations (Discrete Dislocation Dynamics and Molecular Dynamics) to understand how dislocations behave in a confined volume. This project will give us a new insight into fundamental understanding of tensile ductility at the micrometer scale!
Seok-Woo (co-PI) receives the collaborative fund with Profs. Mark Aindow (PI) and Avinash M. Dongare (Co-PI) from US Army Research Laboratory. These three groups will work together on Wire-Arc Additive Manufacturing (WAAM) with US ARL and VRC Metal Systems. Our group will investigate the micro-mechanical properties of WAAMed materials (Inconel and Steel). Additive manufacturing is one of the main research topics in Materials Science and Engineering, and it is wonderful for us to make a contribution to AM technologies!
Shuyang Xiao just passed his proposal defense! Many Congratulations!!! Let’s keep moving forward!
