2017 | AFC ACCOMPLISHMENTS 72 Assessment and Improvement of Handling for High Density Fuel Materials Principal Investigators: J.T.White Collaborators: S.S. Parker, A.T. Nelson Figure 1. Oxygen uptake measurements conducted on powders of U3Si2 and UN in an atmosphere controlled glove box or in air. Processing of high uranium density fuel forms (e.g. U3Si2, UN) in a commercial setting presents challenges because of the propensity of the comminuted powders to adsorb oxygen when exposed to air.The formation of oxides on the surface of the powders is detrimental to the sintering behavior of the powder compact and in the worst-case scenario can even lead to metal fires if the particle size of the feedstock is small enough. To prevent this, feedstock powders were combined with a large volume fraction loading of polymeric binders, which aimed to coat the powders, mitigating surface oxidation and allowing air-handling prior to sintering in a low oxygen-environ- ment furnace. Further study and assessment of this phenomenon will have significant implications in the ability to control sintering and microstructure of mixed oxide transmutation fuels. In addi- tion to the effect on sintering rate, O/M control during densification was observed to strongly affect the final density and microstructure of both (U,Pu)O2 and (U,Ce)O2 pellets.