Investigation of deformation distribution in a round steel rod on the basis of mechanical tests using digital image correlation method

The paper presents the results of an in situ investigation of the evolution of deformation fields during compression of cylindrical and dumbbell-like steel rods at meso- and macroscale levels using digital image correlation method. A different nature of distributions of localized strain regions on the sample surface during compression of cylindrical and dumbbell-like steel rods at stages II and III was established. It was revealed that the change in strain patterns on the sample surface during compression of cylindrical and dumbbell-like steel rods correlates with the stages on the “stress-strain” curves and reflects the change in strain mechanisms.