Irradiation cascades in cementite: 0.1–10 keV Fe recoils

Cementite Fe3C is a metastable carbide present in many steels. Depending on the treatment, the cementite can give rise to varying microstructures such as bainite and pearlite, to name a few. Cementite – being harder than pure iron – makes the resulting steel harder and tougher, enabling it to be used as a construction steel. This type of steels can be used to build fission reactors and may be used for future fusion reactors, where they will be subjected to neutron irradiation from the core. In this work we use molecular dynamics simulations to study the response of pure cementite when Fe atoms are knocked out of their lattice sites by neutrons. The Fe recoils have an energy varying between 100 and 10 keV. It is also shown that defects in cementite are roughly one order of magnitude more aboundant than those in pure iron, even when using the same irradiation conditions and ion energies of at least 5 and 10 keV.