Shearography as a tool to measure creep strain in sealing elastomers

In this work, an application of digital speckle pattern shearing interferometry (shearography) for strain measurement is proposed. This optical technique is implemented to measure strain in elastic materials. Three different sealing elastomers were tested in short-term creep tests in order to assess creep compliance, which is an important mechanical property for viscoelastic materials. The creep tests were carried out applying a constant tensile load to a specimen. An in-plane shearography setup was implemented to measure the creep strains in polymers. Results of creep strains were compared with that obtained with a commercial equipment of digital image correlation (DIC). Although some limitations were found for shearography, it was possible to verify the adaptability of this technique for strain measurement in elastomers.