Strain Analysis by Digital Shearography on an Aluminium Plate with a Geometric Defect under Thermal Loading

Document Type : Original Research Paper


Mechanical Engineering Department, University of Zanjan, Iran.


Digital shearography is a non-destructive and non-contact method for strainmeasurement. In this article strain analysis on defected plate has been studied by the digital shearography method along with a new technique for phase map measurement. For this purpose, an optical set-up known as modified Michelson interferometry system with two diode lasers were developed which are used as coherent optical source. To create phase shifting a piezo-electrical ceramic was used to miniature displacements of interferometry. Phase shifting technique was used to measure phases and differences between the phases.
The strain was measured using the experimental method and compared with numerical analysis results. Behavior of two graphs of experimental measurement and numerical analysis was approximately the same.


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