Strength Evaluation of PyC for TRISO Particles: Development of Equibiaxial Flexural Test

Abstract

For the purpose of evaluating fracture strength of IPyC for TRISO particles, a disc equibiaxial flexural test technique was developed and IPyC-relevant specimens fabricated in a test-run of fluidized-bed chemical vapor deposition were evaluated. It was demonstrated that the test technique developed is effective to determine the apparent fracture strength of thin specimen of PyC. Moreover, true strength was estimated from the acquired apparent strength values based on the result from finite element analysis. The estimated true strength values appeared reasonable for flexural strength of dense PyC. The influence of geometrical features introduced to the specimens due to the specific preparation procedures appeared insignificant.