Study of variable elongations in the uranium-0. 75 weight percent titanium alloy

Technical Report · Tue Nov 01 04:00:00 EST 1977

DOI:https://doi.org/10.2172/5154531· OSTI ID:5154531

Kollie, T G

Tensile specimens cut from the same gamma-quenched-and-aged, 32-mm-thick plate of U-0.75 wt percent Ti (U-0.75 Ti) alloy exhibited elongations that varied between 9.4 and 17.2 percent. Results of microhardness, electron microprobe, chemical analysis, scanning electron microscopy, transmission electron microscopy, ion microprobe analysis, optical microscopy, heat-transfer calculations, and quenching-rate studies led to the conclusion that the variable ductilities were caused by quenching rates from the gamma phase that were too slow and were different across the thickness of the plate. Work of others is cited to support this conclusion. Their work showed that quenching rates of 8 to 50/sup 0/C/s produced a duplex microstructure of ..cap alpha..' and ..cap alpha.. + U/sub 2/Ti phases in the U-0.75 Ti alloy, with ductilities between 7 and 26 percent, respectively. Two solutions to the problem are suggested: (1) add a third element to the alloy to slowdown the ..gamma.. ..-->.. ..cap alpha.. + U/sub 2/Ti transformation so that titanium is retained in solution in the martensitic ..cap alpha..'phase, or (2) substantially improve the heat-transfer coefficients in the quenching bath. The latter suggestion is the near-term solution, whereas the former suggestion is the long-range and better solution.

• Research Organization: Oak Ridge Y-12 Plant, Tenn. (USA)
• DOE Contract Number: W-7405-ENG-26
• OSTI ID: 5154531
• Report Number(s): Y/DA-7421
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360102* -- Metals & Alloys-- Structure & Phase Studies
ACTINIDE ALLOYS
ACTINIDES
ALLOYS
CRYSTAL STRUCTURE
CRYSTAL-PHASE TRANSFORMATIONS
DUCTILITY
ELEMENTS
HEAT TREATMENTS
MECHANICAL PROPERTIES
METALS
MICROSTRUCTURE
PHASE TRANSFORMATIONS
TENSILE PROPERTIES
TITANIUM ALLOYS
URANIUM
URANIUM ALLOYS
URANIUM BASE ALLOYS
URANIUM-ALPHA
URANIUM-GAMMA