Open AccessTwo-dimensional Moiré phase analysis for accurate strain distribution measurement and application in crack prediction
Author(s) -
Qinghua Wang,
Shien Ri,
Hiroshi Tsuda,
Motomichi Koyama,
Kaneaki Tsuzaki
Publication year - 2017
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.25.013465
Subject(s) - moiré pattern , materials science , microscale chemistry , optics , deformation (meteorology) , displacement (psychology) , digital image correlation , shear (geology) , strain (injury) , phase (matter) , composite material , physics , psychology , mathematics education , mathematics , psychotherapist , medicine , quantum mechanics
Aimed at the low accuracy problem of shear strain measurement in Moiré methods, a two-dimensional (2D) Moiré phase analysis method is proposed for full-field deformation measurement with high accuracy. A grid image is first processed by the spatial phase-shifting sampling Moiré technique to get the Moiré phases in two directions, which are then conjointly analyzed for measuring 2D displacement and strain distributions. The strain especially the shear strain measurement accuracy is remarkably improved, and dynamic deformation is measurable from automatic batch processing of single-shot grid images. As an application, the 2D microscale strain distributions of a titanium alloy were measured, and the crack occurrence location was successfully predicted from strain concentration.