Related Experiment Video
Updated: Jul 3, 2026

Micro/Nano-scale Strain Distribution Measurement from Sampling Moiré Fringes
Published on: May 23, 2017
Effects of strain gradients on strain measurements using geometrical phase analysis in the transmission electron
1Texas Materials Institute, University of Texas at Austin, Austin, TX 78712, USA. jayhoon.ch@gmail.com
Abstract:
An analysis of the effects of lens aberrations on the phase contrast images used for strain measurement by geometric phase analysis (GPA) in the TEM shows that errors may result when strain gradients are present and when [formula: see text] at the reciprocal lattice spacing used for the analysis. This conclusion is demonstrated experimentally using a model specimen consisting of a strained Si layer grown epitaxially on a Si-Ge alloy substrate. Image simulations for this model specimen show that strain gradients can introduce oscillations in strain maps when the defocus is not optimized for GPA. This work also makes it possible to identify other potential sources of error in GPA.
More Related Videos
Related Concept Videos
Measurements of Strain
Three-Dimensional Analysis of Strain
Transformation of Plane Strain
Under plane strain conditions, typical for members where one dimension significantly exceeds the others, deformations and resultant strains are...
Stress-Strain Diagram
Mohr's Circle for Plane Strain
Mohr's circle visually represents the strain states under various conditions, which is essential for understanding material behavior. The center of Mohr's...
True Stress and True Strain
In contrast, true stress offers a more precise portrayal. It is computed by dividing the...

