Cold-temperature deformation of nano-sized tungsten and niobium as revealed by in-situ nano-mechanical experiments
Abstract
We constructed and developed an in-situ cryogenic nanomechanical system to study small-scale mechanical behavior of materials at low temperatures. Uniaxial compression of two body-centered-cubic (bcc) metals, Nb and W, with diameters between 400 and 1300 nm, was studied at room temperature and at 165 K. Experiments were conducted inside of a Scanning Electron Microscope (SEM) equipped with a nanomechanical module, with simultaneous cooling of sample and diamond tip. Stress-strain data at 165 K exhibited higher yield strengths and more extensive strain bursts on average, as compared to those at 298 K. We discuss these differences in the framework of nano-sized plasticity and intrinsic lattice resistance. Dislocation dynamics simulations with surface-controlled dislocation multiplication were used to gain insight into size and temperature effects on deformation of nano-sized bcc metals.
Additional Information
© 2014 Science China Press and Springer-Verlag Berlin Heidelberg. Received February 2, 2014; accepted February 28, 2014. The authors gratefully acknowledge the financial support of the Kavli Nanoscience Institute (KNI) through LEE Seok-Woo's prized post-doctoral fellowship, of the Keck Institute for Space Studies at Caltech, and of JRG's NASA Early Career grant. CHENG YinTong acknowledges the financial support of the Caltech SURF program.Additional details
- Eprint ID
- 46044
- Resolver ID
- CaltechAUTHORS:20140603-101604423
- Kavli Nanoscience Institute
- Keck Institute for Space Studies (KISS)
- NASA
- Caltech Summer Undergraduate Research Fellowship (SURF)
- Created
-
2014-06-03Created from EPrint's datestamp field
- Updated
-
2021-11-10Created from EPrint's last_modified field
- Caltech groups
- Kavli Nanoscience Institute, Keck Institute for Space Studies