Research on advanced fuel element for upgrading safety of high temperature gas-cooled reactors, 3; Development on inspection of oxidation resistant fuel element

Honda, Masaki*; Yasuda, Atsushi*; Ohira, Koichi*; Tachibana, Yukio 

For the purpose of upgrading safety of High Temperature Gas-cooled Reactor (HTGR), research on inspection technology for advanced fuel element was conducted with cooperation of JAEA from FY2014 to 2016. The advanced fuel element contains SiC as the matrix material and oxidation resistance is highly improved so that shape and integrity of the fuel element should be maintained even when large unexpected amount of air enters into the core in the air ingress (pipe rupture) accident which is a typical event for the HTGR. For the inspection technology, evaluation and inspection methods on homogeneity of SiC/C matrix and distribution of coated fuel particles as well as dissolution methods of coated fuel particles and SiC/C matrix for evaluation of failure fraction were developed and established.