Sintering behavior of U–80 at.%Zr powder compacts in a vacuum environment

Sintering behavior of U–80 at.%Zr powder compacts in a temperature range from 1100 to 1500 °C in a vacuum of 1 × 10−4 Pa was evaluated. The sintered density depended more on the sintering temperature than on the sintering time. The sintered specimens consisted of the δ-UZr2 matrix with acicular α-Zr precipitates, but it still had un-reacted zirconium when the sintering temperature was 1100 °C. The uranium depletion near the surface of the specimens sintered at temperatures above 1300 °C was detected. Massive Zr(O) grains in the sintered specimen were found, and their formation was restrained when the cooling rate from the sintering temperature was increased.