Fabrication of Uranium-Plutonium Mixed Nitride Fuel Pins for Irradiation Tests in JMTR.

Abstract Pour He-bonded fuel pins containing uranium-plutonium mixed nitride pellets were fabricated for the irradiation tests in JMTR, aiming at understanding the irradiation behavior and demonstrating the feasibility of mixed nitride as an advanced fuel for FBRs. Mixed nitride pellets were prepared by carbothermic reduction of the oxides. One of the fuel pins was fitted with a set of W-Re thermocouples in order to trace the temperature change of pellet center during irradiation. Moreover, ferritic stainless steel was adopted as a cladding material in one fuel pin besides type 316 austenitic stainless steel. In this report, the design and characteristics of mixed nitride fuel pins are described.