[2A04-07] Irradiation Behavior of Fuel Pellets and Claddings

[2A06] Study on forming condition of rim structure and the effect on integrity in a fast reactor fuel

*Masayuki Naganuma¹, Miho Kamei¹, Koji Maeda¹ (1. JAEA)

Keywords:Fast reactor, Fuel, Irradiation behavior, Rim structure, Joyo

As the obscure structure called “rim structure” is formed in LWR high burn-up fuel and affect the integrity, many studies have been conducted. The same structure has also been observed in FR fuel irradiated up to high burn-up in the experimental fast reactor “Joyo”. Thus, fuel behavior analyses were conducted for the irradiation fuel by using the analysis code, and the behavior and forming condition in FR fuel were evaluated. As a result, it was found that there was difference in the forming condition between LWR and FR fuels. Then, the effects of forming rim structure on FR fuel integrity were investigated and confirmed to be benign.