Hyperelastic Ogden Model is commonly used to perform a finite element analysis of large deformation materials, e.g. rubber. To properly identify the parameter value of Ogden Model, not only simple tensile but also planar tensile and equibiaxial tensile test are required. In equibiaxial tensile test, a cruciform specimen is actually used. However, a stress concentration at the corner area of cruciform specimen causes an early rupture, resulting to a difficulty on obtaining mechanical response of the material at large strain condition. In this study, finite element analysis and equibiaxial tensile test using a simple fixture developed by the authors, were conducted to investigate the stress distribution and the stress-strain relationship during equibiaxial tensile loading of cruciform specimen with different corner designs. This study provided new insight into optimum shape of the corner of cruciform specimen.
