STUDY ON THE IMPROVEMENT OF METALLIC URANIUM FUEL. I. THE EFFECTS OF ADDITIVE ELEMENTS, HEAT TREATMENTS AND HOT-ROLLING PROCESS TO THE GRAIN SIZE OF METALLIC URANIUM

Journal Article · Fri Mar 01 04:00:00 EST 1963 · Nippon Genshiryoku Gakkaishi (Japan)

OSTI ID:4714002

Maruya, K; Kimura, J

It is very important to find out the effective method to prevent the anisotropic growth of metallic uranium due to thermal cycling and neutron irradiation in order to achieve high bum-up of metallic uranium fuel. The grain refinement degree of the binary and ternary alloys containing minor additive of Al, Cr, Fe, Mo, Nb, Si, Ti, W, and Zr was studied after the appropriate heat treatments and hot rollings. Major experimental results are summarized as follows: (1) There were remarkable grain refinement of uranium by the addition of Cr, Nb, Mo, and Zr with an adequate heat treatment. These phenomena were considered mainly due to the transformation of nucleation and growth type. In addition, the change of volume on phase transformation, the delay of transformation rate on cooling or quenching, the remaining stress by precipitation of another phase on tempering, and the precipitation of nonmetallic inclusions might have some roles on the grain refinement of uranium. (2) The grain refinement was performed appreciably by the addition of 0.2% Cr, 0.3 to 0.6% Nb, 0.5 to 1.0% Mo, and 1.0to 2.0% Zr, respectively, with the gamma heat treatment. The concentration variation in the range mentioned was not a notable factor in the refinement. (3) The ternary alloys with two additives showed good grain refinement effect on uranium. (4) Hot-rolling process showed no effect on the grain refinement. (5) Ternary alloys of U-Nb (0.3 to 0.6%)-Mo(0.3 to 2.0%) and U-Nb(0.3 to 1.5%)-Zr(>1%) showed the fine grain textures and good workability in hot rolling. These alloys indicate the direction of improvement of metallic uranium. (auth)

• Research Organization: Mitsubishi Atomic Power Industries, Inc., Omiya, Saitama Prefecture, Japan
• NSA Number: NSA-17-022183
• OSTI ID: 4714002
• Journal Information: Nippon Genshiryoku Gakkaishi (Japan), Journal Name: Nippon Genshiryoku Gakkaishi (Japan) Vol. Vol: 5; ISSN NGEGA
• Country of Publication: Country unknown/Code not available
• Language: Japanese

Related Subjects

ALLOTROPY
ALUMINUM ALLOYS
ANISOTROPY
BURNUP
CHROMIUM ALLOYS
COOLING
DEFECTS
ENRICHMENT
FUELS
GRAIN SIZE
HEAT TREATMENTS
HOT WORKING
IMPURITIES
INCLUSIONS
IRON ALLOYS
IRRADIATION
MECHANICAL PROPERTIES
METALS, CERAMICS, AND OTHER MATERIALS
MOLYBDENUM ALLOYS
NEUTRONS
NIOBIUM ALLOYS
PRECIPITATION
QUENCHING
ROLLING
SILICIDES
STRESSES
TEMPERING
TITANIUM ALLOYS
TUNGSTEN ALLOYS
URANIUM
VARIATIONS
VOLUME
ZIRCONIUM ALLOYS