Development of in-situ Nanomechanical Test Methods

(Current Sponsor: NASA Early Career and Department of Energy – Basic Energy Science)

In-situ nano-mechanical tests under a different thermal environment.

The development of one-of-kind in-situ nano-mechanical testing system working under the extreme environments from cryogenic temperature (down to -200 oC) to high temperature (up to +500 oC) 

: We are studying mechanical behaviors at the nanometer scale under different thermal environments (e.g. ductile-to-brittle transition, creep, and fatigue). Through this research, we aim to understand how the combination of size effect and thermal effect influence mechanical behaviors of materials. Furthermore, it is expected that this unique technique can be used for interdisciplinary studies, which involve stress-induced property changes at the nanometer scale. Enjoy in-situ deformation movies below!

Our current laboratory record of the lowest temperature is 37 Kelvin (-236 degree C) with liquid helium cooling.

 

< in-situ nano-mechanical tester with the temperature control capability >

(John Sypek is measuring the sample stage temperature (2018)).

 

<Micro-tension of [0 0 1] niobium at 298 K: Ductile Fracture>

<Micro-tension of [0 0 1] niobium at 56 K: Brittle Fracture >

 

 

Related Publications

  • Gyuho Song, Nicole K. Aragon, Ill Ryu, Seok-Woo Lee, “Low Temperature Failure Mechanism of [001] Niobium Micropillars Revealed by in-situ Cryogenic Micro-Tensile Tests and Dislocation Dynamics Simulations,” Journal of Materials Research (Invited Paper) (2021) – [PDF] [web]
  • Gyuho Song, Vladislav Borisov, William R. Meier, Mingyu Xu, Keith J. Dusoe, John T. Sypek, Roser Valenti, Paul C. Canfield, Seok-Woo Lee*, “Ultrahigh elastically compressible and strain-engineerable intermetallic compounds under uni-axial mechanical loading,” APL Materials 7, 061104 (2019) [PDF] [web]
  • Seok-Woo Lee, Jafary-Zadeh Mehdi, David Chen, Yong-Wei Zhang, Julia R. Greer, “Size effect suppresses brittle failure in hollow Cu60Zr40 metallic glass nanolattices deformed at cryogenic temperature,” Nano Letters 15 5673-5681 (2015)  (Featured at News of American Chemical Society) – [PDF][web].
  • Seok-Woo Lee, Yintong Cheng, Ill Ryu, Julia R. Greer, “Cold-temperature deformation of nano-sized tungsten and niobium revealed by in-situ nano-mechanical experiments,” Science China Technological Sciences 16 184-189 (2014) (invited, and featured on the cover) [PDF][web].
  • Seok-Woo Lee, Lucas Meza, Julia R. Greer, “Cryogenic nanoindentation size effect in [0 0 1]-oriented face-centered and body-centered-cubic single crystals,” Applied Physics Letters 103 101906 (2013) [PDF][web].