Mechanical property measurement at high temperature based on a new disc-shaped specimen

Three-dimensional digital image correlation (3D-DIC) is frequently used to measure mechanical properties of materials. However, the traditional dumbbell-shaped specimen has some limitations for measurment of mechanical properties of materials by use of 3D-DIC at high temperature due to two reasons: (1) its transverse dimension is very small and only a small number of valid speckles can be used in 3D-DIC; and (2) only a small amount of valid information, such as the average deformation of the gauge length, can be used to obtain mechanical properties in one direction. In this work, a new test method based on a disc-shaped standard specimen is first proposed. By use of analytical solutions of a disc under a uniform radial load, and measured results of the full-field displacement of the disc-shaped specimen by 3D-DIC in an effective test region at different high temperatures, mechanical properties at different high temperatures are identified.