Performance of (U, Zr) C-Graphite (Composite) and of (U, Zr) C (Carbide) Fuel Elements in the Nuclear Furnace 1 Test Reactor

摘要

The properties of and reactor test results for two types of nuclear-propulsion-reactor fuel elements containing uranium-zirconium carbide, (0,Zr}C, are reported. Composite fuel elements containing graphite and ~ 35 vol% carbide, along with fuel ele¬ments consisting only of carbide, were tested in Los Alamos Scientific Laboratory's Nuclear Furnace 1 reactor for 109 min at peak power densities of ~ 4500 MW/m3 and temperatures up to 2500 K. Fission-fragment damage to the graphite phase of the composite fuel elements increased the room-temperature thermal resistivity of the matrix ninefold, resulting in unexpected high mass losses of carbon. The carbide elements developed both longi¬tudinal and transverse fractures but did not fragment into small-size particles.