Quantifying microscale drivers for fatigue failure via coupled synchrotron X-ray characterization and simulations

Abstract

During cyclic loading, localization of intragranular deformation due to crystallographic slip acts as a precursor for crack initiation, often at coherent twin boundaries. A suite of high-resolution synchrotron X-ray characterizations, coupled with a crystal plasticity simulation, was conducted on a polycrystalline nickel-based superalloy microstructure near a parent-twin boundary in order to understand the deformation localization behavior of this critical, 3D microstructural configuration. Dark-field X-ray microscopy was spatially linked to high energy X-ray diffraction microscopy and X-ray diffraction contrast tomography in order to quantify, with cutting-edge resolution, an intragranular misorientation and high elastic strain gradients near a twin boundary. These observations quantify the extreme sub-grain scale stress gradients present in polycrystalline microstructures, which often lead to fatigue failure.

Document Details

Document Type
Pub Defense Publication
Publication Date
Jun 24, 2020
Source ID
10.1038/s41467-020-16894-2

Entities

People

  • Can Yıldırım
  • Carsten Detlefs
  • Darren C Pagan
  • Diwakar Naragani
  • Michael D Sangid
  • Paul A. Shade
  • Phil Cook
  • Sven Gustafson
  • Wolfgang Ludwig

Organizations

  • National Science Foundation
  • United States Department of Defense

Tags

Fields of Study

  • Physics

Readers

  • Materials Science (Mechanical Engineering).
  • Powder metallurgy of Titanium alloys.
  • Pulsed Power and Plasma Physics.