Uranium-platinum system

Abstract

The p ha e diagrall\ of the uranium-plati num system \\'as constru cted from data 0 ' )-tained by therma l a na lysis, metallogmphic examina tio n, and X -my diffmction. Th e syste m is characle rized by foUl' intermetalli c co mpounds: U P t, formed pe rilcctoidall.v at, 9(j ] ° C; UPt2, fOfmed perilectically at 1,370° C; UPt3, melting congru enLl. \· at J ,700° C; and U P ts, formed perilectically at, : 1 ,460° C. One eu tectic occurs at 1,005° C and 12 a/o platinu m, and a second at 1,345° C and 87.5 a/o pla tinum. The m aximum solubiliti es a rc .. L5 a/ o u mnium in p latinum and 5 a/o plat inum ill gamma-uranium . Platin um lowc rs Lhe /l:a ll1m a-bl'la lImni1l111 transformalion to 705° C an d the bet.a-alpha transformat ion to . 589° C .

γ-U phase in U-Pt system retained to low temperatures by means of rapid cooling

“…The maximal solubility of Pt in γ-U has been reported not to exceed 5 at.% Pt [5,16,18]. It is crucial that in our study, using the splat cooling, we not only increase the Pt solubility in the bcc U phase but also stabilize this phase to low temperatures, at least up to 15 at.% Pt.…”

“…uranium alloying with 10% weight percent of molybdenum) and U7Mo respectively for the US and European research reactors [4]. This concentration of 7-10wt% Mo) in metallic U is sufficient to obtain the γ-U phase stability.Pt has only about 2 -5 at.% solubility in the γ-U phase at the eutectic temperature [5,15,16], while it forms many very-stable compounds with uranium. A large attention has been focused on the rich-Pt part of the Uranium-Platinum (U-Pt) system, exhibiting 4 intermetallic Recently, we have demonstrated the retention of the cubic γ-U phase in U-T alloys (T= Mo, Zr, Nb) with reduced concentrations of alloying metals by using ultrafast cooling (splat cooling) from the melt to room temperature.…”