Investigation on the Micromechanical Behavior of fiber Reinforced Epoxy with a Semi-automatic Phase Shifting Method

The computer aided prediction of the effective macroscopic material behavior is a goal of research to benefit from the potential of fiber reinforced composite materials. Beside the mechanical characteristic of the material components, an extensive knowledge of the mechanical interaction between the components is necessary. To get experimental information in this field, a novel semiautomatic measurement system was developed. It is able to provide a combination of statistical results on the damage evolution and analytical results to interpret the photoelasticity during the measurement process. This measurement system is applied to the single fiber fragmentation test. The experimental setup enables the microscopic observation of gradual increasing fragmentation of the single embedded fiber and the stress rearrangement at the matrix material at low strain rates. To get information on the stress field out of the dynamic image scene without contact, a four image phase shifting method is used. This presentation describes the developed measurement system and the test setup. Methods to extract characteristic features by applying image processing methods are introduced and the former utilization to obtain comparable mechanic values is explained.