In-Situ Strain Measurement on Al7075 Plate by Using High Energy Synchrotron Light Source

Abstract

In this study, compressive and tensile strain in Al7075 plate have been measured by synchrotron energy-dispersive X-ray diffraction (EDXRD) in conjunction with 4-point bending test under various load up to 1000 lbs(453.6 kg). The compressive and tensile strain are determined by stress related interplanar spacing variation at 111 peak reflection which is considered atomic level strain measurement. The specimen initially shows elastic strain behavior under 400 lbs (181.4 kg) load. However, further load increment applied on sample causes plastic deformation on the regions close edge of the specimen where the biggest stress values in terms of both compression and tension is aroused. Finally, 1000 lbs load is applied on the specimen and major part of the specimen is deformed plastically. Vicinity of body center of sample shows almost no strain formation which is attributed nature of 4-point bending flexural test. Using high energy EDXRD method allow us to reveal precise atomic level strain distribution in Al7075 alloy under different loads.