Abstract
Effect of load hysteresis on fringe pattern in electronic speckle pattern interferometiy has been investigated by uniaxial tensile test of pure aluminum. The fringe pattern in the annealed specimen was perpendicular to the tensile direction which implies uniform tensile deformation. The interval of fringes was decreased with increasing the tensile load, which means strain concentration. The interval of fringe for the pre-loaded specimen was larger than that in the annealed specimen under the yield stress. Moreover, near the yield stress, the fringe pattern shows curvy shape which means the shear deformation or rotation include in the material. Over the yield stress, the fringe pattern was similar to the pattern in the annealed specimen. It was indicated that the differences in the fringe patterns depend on the pre-load stress, and the differences appeared in elastic deformation
