Science China Technological Sciences

, Volume 57, Issue 4, pp 652–662

Cold-temperature deformation of nano-sized tungsten and niobium as revealed by in-situ nano-mechanical experiments

  • Seok-Woo Lee
  • YinTong Cheng
  • Ill Ryu
  • Julia R. Greer
Article Special Topic: Mechanical Behaviour of Micro- and Nano-Scale Materials

DOI: 10.1007/s11431-014-5502-8

Cite this article as:
Lee, S., Cheng, Y., Ryu, I. et al. Sci. China Technol. Sci. (2014) 57: 652. doi:10.1007/s11431-014-5502-8

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.

Keywords

dislocationplasticitymetalnanopillarcryogenics

Copyright information

© Science China Press and Springer-Verlag Berlin Heidelberg 2014

Authors and Affiliations

  • Seok-Woo Lee
    • 1
  • YinTong Cheng
    • 1
  • Ill Ryu
    • 2
  • Julia R. Greer
    • 1
  1. 1.Division of Engineering and Applied ScienceCalifornia Institute of TechnologyPasadenaUSA
  2. 2.School of EngineeringBrown UniversityProvidenceUSA