in-situ cryogenic nano-mechanical tests ln 2 or lhe in 77 k4 k temperature controller (pid) : heater...
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in-situ cryogenic nano-mechanical tests
LN2 or LHe
in
77 K 4 K
Temperaturecontroller (PID): heater control
Coldfinger
Indentertipsample
electron gun
SEM chamber(UHV)
Mechanical dataacquisition
Cu wire
out
Bi-polarheater
heater
Tip coolingassembly
Si diodetemperaturesensors
Ceramic block
Current in-situ cryogenic mechanical testingset-up at Caltech (designed by L. Meza)
The world’s first time cryogenic nanomechanical measurement
Seok-Woo Lee(Postdoc)
in-situ cryogenic nano-mechanical tests
Current in-situ cryogenic mechanical testingset-up at Caltech (designed by L. Meza)
Fundamental understanding ofmechanical behavior of materials atlow temperatures for space applications
COLD!!
D
in-situ cryogenic nano-mechanical tests
SIZE EFFECTS at different temperatures
Nanopillar Size effects size-dependent strength
S.-W. Lee et al. Phil. Mag. (2012)
Theoretical estimation for W
What are you going to do with me?
1. Fabrication of nanostructures
Different sizesDifferent materials
2. Nano-mechanical testing at different temperatures
3. Data analysis (stress-strain) and fundamental understanding(atomistic, dislocation dynamics)
Welcome any enthusiastic SURF students !!!Welcome any enthusiastic SURF students !!!Seok-Woo Lee, [email protected] Lee, [email protected]