A PROGRAM OF BASIC RESEARCH ON MECHANICAL PROPERTIES OF REACTOR MATERIALS. Quarterly Progress Report for the Period Ending March 31, 1963
Deformation and fabrication characteristics of reactor materials are being studied. The effects of room-temperature prestrain on the early flow characteristics of tantalum singie crystals at 77 deg K were analyzed. Results indicated an increase in mobile dislocation density of 16 times in going from 1 to 10% strain at room temperature. Dislocation mobility in Fe-Si crystals was analyzed in terms of their stress dependence. Work on specimen preparation was directed toward preparing and purifying foils. The ratecontrolling process for plastic flow in metals at low temperatures may be the same process as that which produces a low-temperature internal friction maximum, the alpha -peak, found in low-amplitude oscillatory experiments. Methods of identifying the mechanism are being investigated. The model developed for the alpha -peak mechanism is that it is a linear superposition of a distribution of stress-biased, thermally activated relaxation of kinks over potential barriers, Niobium samples were used to test the model in internal-friction measurements. Studies are also being made of the effects of material variables on stored-energy release in deformed iron. Results indicate that the total stored energy in deformed iron is small relative to that in fcc metals, that there is an appreciable grain-size effect in iron, and that the stored-energy releases associated with recovery processes are not large. (M.C.G.)
- Research Organization:
- General Atomic Div. General Dynamics Corp., San Diego, Calif.
- DOE Contract Number:
- AT(04-3)-167
- NSA Number:
- NSA-17-027783
- OSTI ID:
- 4696190
- Report Number(s):
- GA-4227
- Country of Publication:
- United States
- Language:
- English
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A PROGRAM OF BASIC RESEARCH ON MECHANICAL PROPERTIES OF REACTOR MATERIALS. Quarterly Progress Report for the Period Ending June 30, 1962
A PROGRAM OF BASIC RESEARCH ON MECHANICAL PROPERTIES OF REACTOR MATERIALS. Quarterly Progress Report for the Period Ending June 30, 1963
Related Subjects
CREEP
DEFECTS
DEFORMATION
DISLOCATIONS
FABRICATION
FRICTION
GRAIN SIZE
INTERNAL FRICTION
IRON
IRON ALLOYS
LATTICES
LOW TEMPERATURE
MEASURED VALUES
MECHANICAL PROPERTIES
MECHANICS
METALS
METALS, CERAMICS, AND OTHER MATERIALS
MONOCRYSTALS
NIOBIUM
PLASTIC FLOW
REACTORS
RECOVERY
REPORT
SILICIDES
STRESSES
TANTALUM
VIBRATIONS