Analysis of Irradiation Damage of Key Materials in China Initiative Accelerator Driven System

The irradiation resistance capability of structural components in nuclear reactors has a great influence on the system's service life and safety. In this work, the CiADS coupling model between spallation target and subcritical reactor is established by MCNPx2.70, and the atomic dissociation cross sections for CiADS candidate materials are processed by the nuclear data processing software NJOY2016. The irradiation damages for three kinds of stainless steels, 316L, 15-15Ti, SIMP and one kind of ZTA ceramics are calculated and analyzed under three conditions with the number of fuel assemblies of 30, 42 and 72, respectively. When used as CiADS fuel cladding, SIMP steel has the lowest rate of irradiation damage among the three candidate steels. The calculated irradiation damage rate are 1.16, 1.61 and 12.0 dpa/a when the number of fuel assemblies are 30, 42 and 72, respectively. The irradiation damage rate for the fuel cladding made of ZTA materials is much higher than that of the candidate steels. The CiADS center tube suffers the strongest neutron irradiation for the portion near the reaction area between the accelerator beam and the spallation target. The maximum irradiation damage rate is about 2.7 dpa/a for the center tube made of 316L steel when the fuel assemblies are 30.