Mechanical properties of austenitic stainless steels irradiated at SINQ target 4

Saito, Shigeru; Hamaguchi, Dai; Usami, Koji; Endo, Shinya; Ono, Katsuto; Matsui, Hiroki; Kikuchi, Kenji*; Kawai, Masayoshi*; Yong, D.*

Proceedings of 1st International Workshop on Technology and Components of Accelerator-driven Systems (TCADS-1) (Internet), 9 Pages, 2010/03

The research and development for an accelerator-driven system (ADS) to transmute minor actinide (MA) have been progressed. The target beam window of ADS submerged in the reactor will be subjected to high-energy proton and spallation neutron irradiation. To evaluate mechanical properties of irradiated materials, post irradiation examination (PIE) of the STIP (SINQ target irradiation program) specimens was carried out at JAEA. In the present study, PIE on austenitic steels JPCA and Alloy800H irradiated at SINQ target 4 (STIP-II) was conducted. Austenitic steels are preferable as the material for the target beam window of ADS from the view point of DBTT shift, which should be taken into consideration for ferritic / martensitic steels. The irradiation conditions were as follows: proton energy was 580 MeV, irradiation temperatures were ranged from 100 to 450C, and displacement damage levels were ranged from 6.5 to 19.5 dpa. Tensile tests were performed in air at R.T. to 350C. Results of the tensile tests performed at R.T. indicate that irradiation hardening occurred with increasing displacement damage level up to 10 dpa. At higher doses, irradiation hardening seemed to tend to saturate. Degradation of ductility was bottomed around 10 dpa and specimens kept its ductility until 19.5 dpa. All the specimens fractured in ductile manner.