Abstract
The NIRR-1 went through conversion from highly enrich uranium HEU to low enriched
Uranium LEU fuel. The design of the fuel core is such that the cladding materials have
been changed from aluminum to zirconium. The cladding materials may likely
experience neutron dose which is susceptible to degradation of the materials. Hence,
the needs to ascertain the level of degradation of the materials are crucial. Therefore,
we calculate the reaction cross section of Al and Zr target with EMPIRE 3.2.3 modular
nuclear reaction code. The calculated results were compared with measured data from
EXFOR and the Evaluated Nuclear Data (ENDF). Comparative assessment of neutronic
impact of Al and Zr used in the high and low enrich uranium fuel in NIRR-1 were carry
out by compared cross section of Al with Zr results in the reaction channel relevance to
the cladding materials. The results show that 90𝑍𝑟(𝑛. 𝑒𝑙) have high mean cross section
of 1720.30 mb and 90 𝑍𝑟(𝑛. 𝛾) with lower mean cross section of 0.54 mb while
27𝐴𝑙(𝑛. 𝑝) and 27𝐴𝑙(𝑛. 𝛾) high and low mean cross section is 482.5 mb and 0.022 mb
respectively. It was observed that Zr target absorption cross section is better compared
to Al target. This indicates that Zr has proven higher resistance to corrosion and
longevity in terms of degradation as cladding materials.