Abstract: "The effects of a number of ternary additions on the constitution, casting, and fabricating characteristics and the physical properties of aluminum-35 w/o uranium were investigated. Initial investigations were concerned with the effects of 3 w/o ternary additions on the microstructure and press-forging characteristics of the alloy. It was found that additions of this magnitude often introduced extrinsic phases in the alloy. At the 3 w/o level, additions of germanium, silicon, tin or zirconium inhibited the formation of UAl4 and thereby increased the content of the aluminum matrix in the alloy. It was also noted that these additions decreased the pressures required for extruding, and the tin addition also improved the homogeneity of cast shapes. Lead and palladium also improved the homogeneity of the cast material; however, neither of these was an effective inhibitor of UAl4 and free lead was detected in the alloy to which lead had been added at the ternary. From these studies it appears that tin and zirconium are as effective as silicon in enhancing the fabricating characteristics of aluminum-35 w/o uranium alloys, and may prove superior when evaluated on the bases of casting qualities and recycling characteristics."