Author: R. D. NelsonPublisher:
ISBN:
Category : Plutonium
Languages : en
Pages : 40
Book Description
The Beta-alpha and Alpha-beta Transformations in Plutonium Under Applied Stresses
Author: R. D. NelsonPublisher:
ISBN:
Category : Plutonium
Languages : en
Pages : 40
Book Description
Studies on the Alpha-to-beta and Beta-to-alpha Phase Transformations of Plutonium
Author: J. W. AndersonPublisher:
ISBN:
Category : Phase transformations (Statistical physics)
Languages : en
Pages : 62
Book Description
Transformation Kinetics of Plutonium
Author: Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Isothermal reaction curves and T-T-T curves showing the effect of different variables on the beta-alpha transformations in plutonium are presented. Impurity content, stresses, beta heat-treating time and temperature, hydrostatic pressing, specimen size, and thermal cycling influenced the kinetics of the beta- alpha transformation. Decreasing the impurlty content increased the rate of transformation. High tensile stress retarded the beta-alpha transformation. Increasing the beta heat-treating time and temperature markedly decreased the rate of transformation. Hydrostatic pressing at 90,000 psi accelerated the beta- alpha transformation under pressure but decreased any subsequent beta-alpha transformations by as much as two orders of magnitude. Specimen size had no effect on the start of the transformation but increasing the specimen size from 0.010 to 0.37 inch decreased the rate of completion of transformation several orders of magnitude. Thermal cycling less than 15 cycles did not affect the rate of transformation. The density of high purity plutonium during hydrostatic pressing at l80 deg C and cooling under pressure increased from 19.60 to 19.65 g/ cm3to 19.70 to 19.75 g/cm3. This increase was shown to be attributed to decreasing the volume of microcracks rather than transformation of any metastable beta phase. A T-T-T curve of the alpha-beta transformation is given which shows the start of the transformation is 16 hours at 116.5 deg C with the rate decreasing extremely rapidly with decreasing temperature. The times for the start and completion of the transformation were significantly shorter than the early work reported. The faster rate was attributed to less impurities, The gamma-beta-alpha and alpha-beta-gamma transformations are discussed also. Isothermal reaction curves and T-T-T curves for these transformation are included. (auth).
Kinetics of the Alpha Beta Transformation of Plutonium Near the Equilibrium Temperature
Author: Scientific and Technical Aerospace Reports
Author: Transformation Kinetics of Plutonium
Author: R. D. NelsonPublisher:
ISBN:
Category : Chemical kinetics
Languages : en
Pages : 126
Book Description
Investigation of the Stresses Induced During the Beta-to-alpha Phase Transformation in Unalloyed Plutonium
Author: Brent J. BeerPublisher:
ISBN:
Category : Phase rule and equilibrium
Languages : en
Pages : 282
Book Description
Nuclear Science Abstracts
Author: Kinetics of the Beta-alpha Transformation in Pure Plutonium
Author: Supplement to "Studies on the Equilibrium Temperature for the Plutonium Alpha-Beta Transformation."
Author: Publisher:
ISBN:
Category :
Languages : en
Pages : 23
Book Description
The cited paper presents data which establishes the equilibrium temperature for the alpha-beta transformation of Pu at 117.0 ±0.5°C. This was observed by following the electrical resistance change in thin, high purity, mixed-phase specimens as they were thermally cycled near the transformation temperature. As expected the time required for small phase changes near the equilibrium temperature was long. Data regarding the mechanisms of the alpha-beta and beta-alpha transformations or rates as a function of temperature were not presented.