Application of Digital Image Correlation in Uniaxial Tensile Test

Abstract

Application fields of non-contact measurement techniques have been recently increasing by means of optics and technological development in measurement applications. Digital image correlation (DIC) is the one and powerful non-contact measurement method that can be used to obtain elongation and strain as well. It is versatile and flexible measurement method can be adopted to many traditional test experiments such as tensile, compression, and bending in order to calculate mechanical properties of materials. In this study, DP600, DP800 and DP980 steel materials were performed to uniaxial tensile test and DIC technique was used to determine local strains in terms of comparison in different regions at the fracture area. While performing experiments, commercial DSLR camera was installed to capture videos under the white led lighting which is needed to decrease visual blurring and keep contrast as constant. Recorded videos were analyzed with VIC-2D software in an effort to calculate strain data. As a result, it was showed that the strains at the fracture area that were measured with DIC were higher than those measured which out of the fractured area and concluded that DIC method was appropriate and efficient technique to measure local strains in traditional uniaxial tensile test.

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