Measurement of Strain Distribution and Volume Ratio in Tensile Test of Circular Shaft Specimens of steel and Consideration of Stress-Strain Relation

Abstract

Displacement distribution in circular shaft specimen of steel during tensile test was measured using digital image correlation (DIC) method. Video image of the specimen surface was continuously taken during tensile test and static images were selected from the movie file after the test. Distributions of strains in axial and in vertical directions were obtained from the displacement distribution and also diameter of the specimen was estimated based on strain distribution in vertical direction to the specimen axis. Distributions of strain and diameter of the specimen were observed during whole tensile test and stress-strain relation based on local deformation was considered.