Composition controlled new materials production using transmutation reaction under irradiation of high energy particles

The large problem in the materials for nuclear reactors and fusion reactors is the deterioration of material characteristics due to irradiation damage. Recently it has become a large problem that the elements produced by the nuclear reaction in neutron irradiation process exert influence remarkably to the properties of reactor materials. The nuclear transformation elements which have become noteworthy in reactor materials are helium and hydrogen introduced into reactor materials by (n, alpha) and (n, p) reactions. The nuclear transformations for producing osmium, rhodium and gold are explained, and the synthesis of materials utilizing nuclear transformation reaction is possible. The applications to the production of Al-Si alloy, V-Cr alloy and the formation of Zn and Ni by the nuclear transformation of Cu isotopes are described. The applications to the production of GaAs from Ge and the production of n-type Si semiconductors are explained. Most of the elements that become the basis of practical materials are composed of two or more isotopes that have different numbers of neutrons. (K.I.)