Avaliação das propriedades elásticas de materiais isotrópicos e ortotrópicos por Correlação Digital de Imagens (DIC)

Abstract

The exponential increase in demand for new materials, combined with growing demands for sustainability, has driven the development of materials science, increasing demands on conventional manufacturing, control and characterization processes and techniques. To keep up with this global trend, methods for analyzing materials and structures also need to be improved. Following this trend, this work focuses on studying the application of the Digital Image Correlation Technique (DIC) in the Assessment of Elastic Properties of Isotropic and Orthotropic Materials. Digital image correlation (DIC) is a wide-field optical technique that consists of analyzing the surface of reference and deformed images, to determine displacement and deformation fields in different materials. This research proposes the use of an algorithm in Matlab® to apply the DIC technique. For this purpose, test specimens made of polyester matrix composite with red mud were used, made of aluminum, in part of which defects and steel were inserted. The samples were tested under traction according to ABNT NBR 7549, ASTM D3039 standards. During the tests, extensometers and strain gauges were used in the longitudinal and transverse directions of request, with the purpose of, from the identification of broad deformation fields via DIC, comparing the average deformations obtained in both directions, seeking to identify possible mechanisms of failures acting on the sample. The results demonstrate that the average deformations obtained via DIC are comparable to conventional methods, and it was possible to identify surface defects inserted in the samples by evaluating the deformation fields, enabling the study of their detection using the DIC technique.