Experimental and simulation study on stress concentration of graphite components in tension

Nuclear graphite is a typical quasi-brittle material used in nuclear reactors. Damage can easily generate and accumulate under loads due to widespread defects (such as cracks or holes) inside the material and thereby cause the degradation of material properties. Studies have shown that nuclear graphite exhibits different damage evolution behaviours under tensile and compressive loading. In this paper, experiments were first carried out to measure the stress concentration factors of L-shaped graphite specimens with different corner radii subjected to tension. Subsequently, finite element models with and without damage evolution were established, and different damage evolution laws were considered for tension and compression in the damage model. The importance of damage on stress concentration prediction of graphite components was emphasized by comparing the experimental and numerical simulation results.