Papers by Author: Jonathan S. Joy

Abstract: The blending of lithium hydride with both crystalline and amorphous boron has been investigated in order to create single, stable inorganic materials. Loadings up to 20% have been achieved in order to ascertain the ability to evenly distribute the particles throughout the lithium hydride matrix. Initial X-ray data suggests that amorphous boron is more evenly distributed throughout the lithium hydride owing to its smaller particle size but pressing the material results in a lower overall density than the corresponding crystalline boron / lithium hydride mix.

Abstract: AWE is a world center of excellence in lithium hydride technology and has 50 years of experience in research, characterisation and manufacture of lithium hydride artifacts. Because of its affinity for water, lithium hydride is handled under ultra-dry conditions, in argon or nitrogen filled glove boxes. Even when handled with extreme care though it still picks up traces of moisture in the gas atmosphere and the resulting material, when fabricated into shapes, continually outgasses very low levels of hydrogen. Lithium hydride is a pale grey polycrystalline solid, compacted to less than 100% theoretical density. The generation of hydrogen gas is a major concern as it may be fielded in sealed metal containers that are susceptible to attack by hydrogen. For this reason, the outgassing has been the subject of intensive study. It is therefore surprising that its chemical properties are not better understood, properties that are fundamental to developing a model of the materials ageing behaviour. This paper will present our current research investigating the mechanisms of hydrogen outgassing, enhancing specific analytical techniques to probe the unique chemistry, and using our knowledge to improve resultant ceramic components.