Numerical and experimental investigation of defect detection incomposite materials by means of digitalshearography

Shearography is a laser-based technique for full-field,noncontactingmeasurement of surface deformation(displacement or strain). It was developed to overcomeseveral limitations of holography by eliminating thereference beam. It does not require special vibrationisolation; hence, it is a practical tool that can be used in afield/factory environment. In this article, a numericalprocedure was developed to simulate shearographic fringepatterns using finite element analysis and supplementaryprogramming. The modeling method was evaluated usingexperimental tests in in a glass fiber reinforced compositeswith mechanical loading for detection of artificial cracks.Crack-type defects were simulated by cutting severalgrooves with different sizes and orientations in an ۸layerfiber reinforced composite plate. In comparison withnumerical and experimental results, It has been showedthat for each distinct case of nondestructive testing, athermal loading diagram can be extracted to get credibleresults.

کلیدواژه ها:

Manufacturing defects ، nondestructive test ، digital shearography ، finite element method