Lee group attended 2020 TMS meeting at San Diego (Feb. 23-27)!

Five presentations was given in 2020 TMS meeting.

• Gyuho Song: Ductile-to-brittle transition of micron-sized niobium at cryogenic temperatures (Symposium: Mechanical Behavior at the Nanoscale V, 8:30am, 2/26 (Wed.))
• Tyler Flanagan (1): The effects of defects on the mechanical properties of Au microparticles (Symposium: Advanced Characterization Techniques for Quantifying and Modeling Deformation, 11:30am, 2/27 (Thurs.))
• Tyler Flanagan (2): The effects of supersonic impacts on the micromechanical properties of Al6061 cold spray deposits (Symposium: Mechanical Behavior at the Nanoscale V, 2pm, 2/25 (Tue.))
• Jessica Maita: Role of grain boundaries in plasticity and fracture of nanocrystalline MgAl₂O₄ (Symposium: Mechanical Behavior at the Nanoscale V, 10:20am, (Mon.))
• Shuyang Xiao: Effects of microstructures on superelasticity of CaFe₂As₂ single crystal (Symposium: Mechanical Behavior at the Nanoscale V, 4pm, 2/26 (Wed.))

Zhongyuan passed his qualifying exam. Congratulations! It is the time to do research! 🙂

UConn MRS Chapter had a great annual night event at Boston (during MRS)! Thank you so much for Jessica (president)’s great support!

See you next year!

Tyler receives the UConn Doctoral Dissertation Fellowship! Many Congratulations!

The information of the doctoral dissertation fellowship is available at the link below.

https://grad.uconn.edu/financing/fellowships/dissertation/

Seok-Woo is selected as a Castleman Term Professor in Engineering Innovation.  This award was established to recognize outstanding faculty members who embody exceptional achievements and the deep commitment to research, education and outreach. The appointment for the Castleman Term Professorship will start on January 1, 2020 and will continue for three years (or until promoted to Full Professor).

The following presentations were given by Lee’s group at the 2019 MRS Fall Meeting! Wonderful Jobs!

Jessica was nominated for the best poster award! (Almost there!)

• Seok-Woo Lee: In-situ micromechanical characterization of iron-based high temperature superconductors (oral) (Session: MQ03.05 (Predictive Synthesis and Advanced Characterization of Emerging Quantum Materials)
• Gyuho Song: Ductile-to-brittle transition of micron-sized niobium at cryogenic temperatures (oral) (MS01.07 (Extreme Mechanics)
• Tyler Flanagan: Shock-induced softening in single crystal magnesium (oral) (MS01.07 (Extreme Mechanics)
• Jessica Maita: Role of grain boundaries in plasticity and fracture of nanocrystalline MgAl₂O₄ (poster)(Session: MQ03.06 (Mechanics of Nanocomposite and Hybrid Materials)
• Shuyang Xiao: Effects of microstructures on superelasticity of CaFe₂As₂ single crystal (Session: MS01.10 (Extreme Mechanics)

Zhongyuan joined the Lee group! Welcome.

Zhongyuan will work on the development of hybrid organic-inorganic polymer nanocomposites. This work will be supported by NSF-MoMS (Mechanics of Materials and Structure).

<Zhongyuan Li>

Seok-Woo gave a Condensed Matter Physics seminar at UConn on 10/09/2019.

The title of presentation was “Superelasticity of ThCr2Si2-type intermetallic compounds at the micrometer scale”.

Lee group attended the ECI Nanomechanical Testing in Materials Research and Development VII at Malaga, Spain!

The following presentations were given by my group.

• Gyuho Song: Superelasticity of ThCr₂Si₂-structured intermetallic compounds at the micrometer scale (oral)
• Gyuho Song: Micromechanical characterization of single-crystalline niobium at low temperature (poster)
• Tyler Flanagan: Nanoindentation properties of shock compressed single crystal magnesium (poster)
• Jessica Maita: Atomic arrangement and mechanical properties of chemical vapor deposited amorphous boron (poster)

(If you click an image, you can see its large image.)

Hetal’s paper was published at Scripta Materialia! Congratulations!

Hetal D. Patel, Seok-Woo Lee, “Spherical indentation on tungsten single crystal: transition from source-controlled plasticity to bulk plasticity,” Scripta Materialia, 175, 16-19 (2019) [PDF] [web]  – Hetal D. Patel (undergraduate student)

Hetal has worked at the Lee group nearly for her entire undergraduate time, and finally got a publication! She recently started her PhD degree at MSE in UC Berkeley. I wish Hetal a success!

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ABSTRACT

Spherical nanoindentation was performed on tungsten single crystal to investigate the effects of tip radius on the pop-in stress. The results show that the pop-in stress decreases as the tip radius increases. A statistical model with randomly distributed dislocation sources captures experimentally observed source-controlled indentation size effect. The discrepancy between model and experimental data especially for a large tip was corrected by considering the collective activation of multiple dislocation sources. Our results provide a quantitative insight into the understanding of the transition from source-controlled plasticity to bulk plasticity under spherical nanoindentation.