FISSION FRAGMENT DAMAGE TO CRYSTAL STRUCTURES

Technical Report · Mon Feb 01 04:00:00 EST 1960

OSTI ID:4174771

Berman, R M; Bleiberg, M L; Yeniscavich, W

Al/sub 2/O/sub 3/ and ZrSiO/sub 4/ show little change in properties when exposed to 10/sup 18/ to 10/sup 19/ nvt of thermal neutrons. When, however, a source of fission fragments is provided in the form of a UO/sub 2/ dispersant, the grain boundaries and the peaks of the x-ray-diffraction profile disappear on irradiation. The crystal structure of U/sub 3/O/sub 8/ is also destroyed when irradiated in-pile. Al/sub 2/O/sub 3/ was observed to increase about 30% in volume concurrent with the destruction of its crystal lattice. Calculations indicate that only a small proportion of the atoms are displaced by the fission fragment through elastic collisions or other applicable mechanisms. It is suggested that the fission fragments act indirectly, through anisotropic effects which distort the lattice and render it unstable. There is apparently a considerable group of materials that exhibit this property; this places a serious limitation on the materials suitable for use within the range of fission fragment recoil. In contrast to this behavior, a number of ceramic materials having a cubic crystal structure exhibit excellent stability in-pile. These materials include UO/sub 2/ and UO/sub 2/ + ZrO/sub 2/. (auth)

• Research Organization: Westinghouse Electric Corp. Bettis Atomic Power Lab., Pittsburgh
• DOE Contract Number: AT(11-1)-GEN-14
• NSA Number: NSA-14-013020
• OSTI ID: 4174771
• Report Number(s): WAPD-T-1125
• Country of Publication: United States
• Language: English

Related Subjects

ALUMINUM OXIDES
ANISOTROPY
ATOMS
CERAMICS
COLLISIONS
CRYSTALS
DEFECTS
DEFORMATION
DIFFRACTION
DISPERSIONS
DISTRIBUTION
EXPANSION
FISSION PRODUCTS
GRAIN BOUNDARIES
LATTICES
METALS, CERAMICS, AND MATERIALS
RADIATION EFFECTS
RECOILS
STABILITY
THERMAL NEUTRONS
URANIUM DIOXIDE
URANIUM OXIDES
X RADIATION
ZIRCONIUM OXIDES
ZIRCONIUM SILICATES