2013 Fiscal Year Final Research Report

Irradiation creep and the underlying mechanisms of ion-irradiated SiC

Research Project

Project/Area Number	24760715
Research Category	Grant-in-Aid for Young Scientists (B)
Allocation Type	Multi-year Fund
Research Field	Nuclear engineering
Research Institution	Kyoto University
Principal Investigator	KONDO Souske 京都大学, エネルギー理工学研究所, 特定助教 (10563984)
Project Period (FY)	2012-04-01 – 2014-03-31
Keywords	炭化ケイ素 / 照射クリープ / スウェリング
Research Abstract	Irradiation creep in SiC was studied by an ion-irradiation under various conditions. The tensioned surfaces of bent thin samples were irradiated with Si ions up to 3 dpa at 553K-1473K, which is referred to as a single-ion test. Additional He ions were irradiated simultaneously in the dual-ion test to study the effects of transmuted He on irradiation creep. Irradiation creep was found at >673K in the single-ion case, where a linear relationship between irradiation creep and swelling (C/S) was observed at 673-1073K for all stress levels. The proportional constant of the C/S relationship was strongly dependent on temperature and stress. On the basis of the TEM study, anisotropic distribution of SIA clusters was suspected to be the primary creep mechanism. For the dual-ion cases, irradiation creep was very limited at temperatures of 673-1073K. TEM study indicated that helium inhibited the stable growth of SIA clusters and prevented them from exhibiting anisotropic distribution.