Process for controlling end-point density of sintered uranium dioxide nuclear fuel bodies and product

Claim 1

A PROCESS FOR CONTROLLING END-POINT DENSITY OF A SINTERED URANIUM DIOXIDE NNUCLEAR FUEL BODY BY FORMING DISCRETE LOW DENSITY POROUS REGIONS THEREIN COMPRISNG THE STEPS OF PROVIDING URANIUM DIOXIDE POWDER HAVING AN OXYGEN TO URANIUM ATOMIC RATIO RANGING FROM ABOUT 2.00 TO 2.25 AND RANGING IN SIZE UP TO ABOUT 10 MICRONS, ADMIXING SAID URANIUM DIOXIDE POWDER WITH A PRECURSOR TOO URANIUM DIOXIDE HAVING AN AVERAGE AGGLOMERATED PARTICLE SIZE SIGNIFICANTLY LARGER THAN THAT OF THE URANIUM DIOXIDE POWDER AND RANGING FROM ABOUT 20 MICRONS TO ONE MILLIMETER, SAID PRECURSOR BEING A SOLID AND HAVING A DENSITY LOWER THAN THAT OF URANIUM DIOXIDE, FORMING THE RESULTING MIXTURE INTO A GREEN BODY HAVING A DENSITY RANGING FROM ABOUT 30% TO 70% OF THEORETICAL, SAID GREEN BODY HAS A STRUCTURE COMPOSED OF A SUBSTANTIALLY UNIFORM MATRIX OF THE URANIUM DIOXIDE POWDER WITH DISCRETE LOW DENSITY REGIONS OF SAID PRECURSOR THEREIN, SAID PRECURSOR BEING USED IN AN AMOUNT WHICH RESULTS IN SAID DISCRETE LOW DENSITY REGIONS IN THE GREEN BODY RANGING FROM ABOUT 5% TO 25% BY VOLUME OF SAID GREEN BODY, HEATING SAID GREEN BODY TO DECOMPOSE SAID PRECURSOR BEFORE REACHING SINTERING TEMPERATURE,AND SINTERING THE BODY TO PRODUCE A SINTERED BODY HAVING DISCRETE LOW DENSITY POROUS REGIONS WITH A DENSITY SIGNIFICANTLY LOWER THAN THAT OF THE SURROUNDING SINTERED URANIUM DIOXIDE, SAID DISCRETE LOW DENSITY POROUS REGIONS REDUCING THE END-POINT DENSITY OF SAID SINTERED BODY BY AT LEAST 2%, SAID SINTERED BODY HAVING AN END-POINT DENSITY RANGING FROM 85% TO 95% OF THEORETICAL.