Structural Characteristic Length in Metallic Glasses


Akcay F. A.

JOURNAL OF MECHANICS, vol.36, no.2, pp.255-264, 2020 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 36 Issue: 2
  • Publication Date: 2020
  • Doi Number: 10.1017/jmech.2019.64
  • Title of Journal : JOURNAL OF MECHANICS
  • Page Numbers: pp.255-264
  • Keywords: Metallic glasses (MGs), Characteristic length, Fracture toughness, Critical crack tip opening displacement (CTODc), FRACTURE-TOUGHNESS DETERMINATION, NOTCH TOUGHNESS, BEHAVIOR, DEFORMATION, FATIGUE, ALLOYS, FLOW

Abstract

Fracture of materials at the microscopic level involves a characteristic length related to microstructure. However, a clear structure-property relationship is still absent in metallic glasses. Therefore, a physics-based expression is derived for the characteristic length (relevant to brittle fracture) in metallic glasses (MGs) in order to link the microscopic material features controlling the fracture process to the macroscopic material parameters. The derived characteristic length is associated to micro/nano structural fracture patterns, critical crack tip opening displacement as well as fracture toughness. Characteristic lengths of various metallic glasses are determined using the proposed expression and compared to the experimental results. Theoretical results are in very good agreement with the experimental results of various metallic glasses. Furthermore, the contribution of characteristic length as well as macroscopic material parameters such as Poisson's ratio, yield strength, and Young's modulus on fracture toughness (and fracture energy) is investigated and compared to the experimental results.