Reactor control rod element

摘要

A neutron absorbing pin including at least, a neutron absorber, a thin-wall pipe surrounding the neutron absorber, and a cladding disposed at a distance from the thin-wall pipe. In the neutron absorbing pin, the difference between the coefficient of thermal expansion ( alpha 1) of the neutron absorber and the coefficient of thermal expansion ( alpha 2) of the thin-wall pipe has an absolute value of | alpha 2- alpha 1|