A compact polariscope/shearing interferometer for mapping stress fields in bimaterial systems
A compact optical device, which is a combination of a polariscope and a shearing interferometer (PSI), is described for mapping stress fields in bimaterial systems. The PSI device uses commercially available wave plates, and a calcite crystal for beam duplicating. It can operate in a variety of modes, including as a circular polariscope and as a shearing interferometer. In its polariscope mode, it can be used on birefringent materials such as Homolite and epoxy; in its shearing mode, it can be used on optically isotropic materials such as polymethylmethacrylate (PMMA) and glass. As an example, the device is used to obtain full-field maps of stress fields in the vicinity of an interfacial crack in an epoxy-PMMA bimaterial plate.
KeywordsEpoxy Mechanical Engineer Calcite Fluid Dynamics PMMA
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