Measurement and evaluation of strain fields in T23 steel based on digital image correlation method

Surface strain fields of the designed compact tension (CT) specimens were investigated by digital image correlation (DIC) method. An integrative computer program was developed based on DIC algorithms to characterize the strain fields accurately and graphically. Strain distribution of the CT specimen was predicted by finite element method (FEM). Good agreement is observed between the surface strain fields measured by DIC and predicted by FEM, which reveals that the proposed method is practical and effective to determine the strain fields of CT specimens. Moreover, strain fields of the CT specimens with various compressive loads and notch diameters were studied by DIC. The experimental results can provide effective reference to usage of CT specimens in triaxial creep test by appropriately selecting specimen and experiment parameters.