Browsing by Author "Bannister, MJ"

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    Sinterability studies on various BeO powders - a second report
    (Australian Atomic Energy Commission, 1965-06) Bannister, MJ
    Six sulphate-derived beryllium oxide powders have been studied and a comparison made of their powder properties and sintering behaviour. Powders containing segregated impurities showed irregular grain growth and those with strongly bonded aggregates showed internal cracking during sintering. All powders sintered less readily in hydrogen than in nitrogen. Semi-empirical equations are presented relating sintering temperature and the grain size at any sintered density to the powder surface area and the green density of the pressed compact.
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    Sintering by volume diffusion
    (Australian Atomic Energy Commission, 1964-06) Bannister, MJ
    The process of sintering by volume diffusion has been subjected to a critical review. Various stages in the sintering process have been identified. It has been shown that sintering is most effective when the porosity takes the form of continuous pore channels along three—grain edges. The conditions determining when this stage finishes have been derived, and the effect of the subsequent stage on the sintering kinetics has been predicted. The available kinetic data for the sintering of BeO have been reviewed.
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    A survey of the storage behaviour of uranium dioxide
    (Australian Atomic Energy Commission, 1967-07) Bannister, MJ
    The storage behaviour of uranium dioxide powder is reviewed. Topics covered include the amount of oxygen taken up under storage conditions, the basic oxidation processes, the effects of extra oxygen on the fabrication and irradiation behaviour of uranium dioxide, the pyrophoric reaction of uranium dioxide powders in air, the stabilization of uranium dioxide against oxidation, and the effectiveness of sealed containers. The pyrophoric process in air at room temperature is shown to be the result of rapid chemisorption of oxygen, and a theory explaining this effect is developed. Equations are also derived to describe the overall oxidation behaviour in air at room temperature, and they are found to agree with what few experimental data are available.