How the toughness in metallic glasses depends on topological and chemical heterogeneity

Abstract

This article reports and explains how the cavitation in metallic glasses is controlled by topological structure as well as chemical heterogeneity. It is shown that in the tough metal–metalloid Pd-Si metallic glass, cavitation initiation is controlled by both chemical separation and particular types of low coordination number (LCN) Pd-centered polyhedra. In contrast, cavitation in the brittle metal-metal Cu-Zr metallic glass is only governed by topological factors. A high-energy barrier to form LCN polyhedra and the process of chemical separation during cavitation initiation are believed to contribute to a higher metallic glass toughness, thereby allowing a larger plastic strain to fracture.

Document Details

Document Type
Pub Defense Publication
Publication Date
Jun 15, 2016
Source ID
10.1073/pnas.1607506113

Entities

People

  • Danielle O. Duggins
  • Konrad Samwer
  • Marios D. Demetriou
  • Michael C. Floyd
  • Qi An
  • William Andrew Goddard III
  • William L. Johnson

Organizations

  • California Institute of Technology
  • Division of Materials Research
  • United States Army Research Laboratory
  • University of Göttingen

Tags

Fields of Study

  • Materials science

Readers

  • Materials Science and Engineering.
  • Nanocomposite Materials Science
  • Powder metallurgy of Titanium alloys.