The Compressive Strength of Nuclear Graphite (I)
Effect of Neutron-Irradiation and Fracture Criterion
1976 Volume 1976 Issue 87 Pages 123-129
Details
1976 Volume 1976 Issue 87 Pages 123-129
Studies were made on the effect of neutron-irradiation on the compressive strength of some graphites for the HTGR. Irradiation temperature and neutron fluence were 200-1100°C and 4×1021 n/cm2 (E>0.18MeV), respectively. Fracture criterion and the statistical properties of the irradiated graphites were also investigated here. The materials used were several imported graphites such as 7477/PT, IM2-24, IM-2, H327 and some domestic ones.
Increase in strength caused by irradiation was most pronounced in the case of anisotropic petroleum coke graphite, while only small amount of the increase was observed for the fine-grained isotropic graphite. Constant energy criterion, (σ/σ0) 2 ∝ Y/Y0, was obtained, when both the fluence and irradiation temperature were low. This was also obeyed in the case of high temperature and high fluence for the isotropic graphites. Here, σ0, σ and Y0, Y are the compressive strengths and Young's moduli before and after irradiation, respectively.
