Measurement of tensile strength of nuclear graphite based on ring compression test

Nuclear graphite is a type of quasi-brittle material, in which the ratio of the tensile strength to the compressive strength is higher than that of ceramic and hard rock materials. In this case, it is difficult to achieve a perfect splitting mode when the Brazilian splitting test is used to measure the tensile strength of such materials, leading to significant measurement errors. In this study, a ring compression test for measuring the tensile strength of the nuclear graphite material was proposed, and related principles and experimental verification were presented. The results showed that a regular tensile failure mode can be achieved using ring compression tests, and the tensile strength of nuclear graphite can be accurately measured. Furthermore, it was found that the accuracy obtained from ring compression tests was much higher than that from Brazilian splitting tests.