Microstructure evolution in metal nanostructures under extreme conditions of temperature and strain rate

V. Gupta, N. M. Ghoniem, R. Crum, G. Po, D. Seif, S. V. Prikhodko, H. A. Colorado, B. Ramirez, C. Gámez

Research output: Contribution to journalArticlepeer-review

Abstract

This paper explores a fundamental connection between ductility and domain size in metallic solids under extreme conditions of cryogenic temperatures and strain rates (108s-1). A series of novel experiments, backed by multiscale modelling and transmission electron microscopy (TEM) analysis, are presented that involve loading of TEM-ready single crystal nanopillar samples of Cu of varying lengths (50 nm to 1mm) and aspect ratios (50 nm to 100 nm in diameter) by laser-generated stress waves of sub-nanosecond rise times, under extreme conditions of strain rate (>108s-1) and temperature (100K). The nucleation stress for Shockley partials, which can be taken as a proxy for the onset of ductile deformation, was measured to be only 1 GPa. This is an order of magnitude lower than the previously measured values of 35 GPain bulk geometries. TEM observations show remarkable ability of the material to re-arrange itself through motion of dislocations to form subgrain boundaries within a very short duration of only few nanoseconds.

Original languageEnglish (US)
Pages (from-to)201-208
Number of pages8
JournalProceedings of the Indian National Science Academy
Volume82
Issue number2
DOIs
StatePublished - Jun 2016
Externally publishedYes

Keywords

  • Ductility
  • FCC Metals
  • MD Simulations
  • Shock Loading
  • TEM

ASJC Scopus subject areas

  • Biochemistry, Genetics and Molecular Biology(all)
  • Physics and Astronomy(all)

Fingerprint

Dive into the research topics of 'Microstructure evolution in metal nanostructures under extreme conditions of temperature and strain rate'. Together they form a unique fingerprint.

Cite this