摘要:
A method of making refractory alkaline earth silicate fibres from a melt, comprises the use as an intended component of alkali metal but not including where at least 75mol% of the alkali metal is potassium to improve the mechanical properties of the fibre in comparison with a fibre free of alkali metal.
摘要:
A glass fibre formable from a melt by a rotary process and having a diameter less than 5µm and comprising in weight percent: SiO2 62 to 75 wt%, alkaline earth metal oxide 13 to 25 wt%, alkali metal oxide 8 to 15 wt%, B2O3 0 to 8 wt%, M2O3 0.5 to 3 wt% in which M is Al, a transition element, a lanthanide or a mixture thereof with these named ingredients comprising greater than or equal to 90 wt% and less than or equal to 100 wt% of the glass composition provides blankets having superior temperature resistance to conventional glass wools, and superior insulating performance (i.e. lower thermal conductivity) than an alkaline earth silicate fibre while being soluble in body.
摘要:
A dense, self-sintered silicon carbide/carbon-graphite composite material and a process for producing the composite material is disclosed. The composite material comprises a silicon carbide matrix, between 2 and 30 percent by weight carbon-graphite, and small amounts of sintering aids such as boron and free carbon. The silicon carbide has an average grain size between 2 and 15 mu m, and the carbon-graphite has an average grain size between 10 and 75 mu m, the average grain size of the carbon-graphite being greater than the average grain size of the silicon carbide. The composite material has a density of at least 80 percent of theoretical density as determined by the rule of mixtures for a composite material. This density is achieved with minimal microcracking at a high graphite loading with large graphite particles. The composite material exhibits good lubricity and wear characteristics, resulting in improved tribological performance. The process for producing the composite material uses a carbon-bonded graphite comprising at least 5 percent by weight carbon-precursor binder.
摘要:
A method for making alloy materials for use in the manufacture of synthetic diamonds, in which the alloy materials are manufactured chemically using a wet chemical method.
摘要:
A fuel cell or electrolyser stack comprises countercurrent radially directed fuel and oxidant flow fields on either side of a membrane electrode assembly. A first reactant may flow radially outwardly from a manifold to a first reactant drain and a second reactant may flow inwardly from the edge of the assembly to a second reactant drain.
摘要:
A composite material comprises inorganic-bonded alkaline earth silicate fibres in which any bonding agents or fillers comprise low amounts of aluminium so that the composite material comprises less than 1 % by weight aluminium expressed as Al2-O3.
摘要:
The use of P2O5 and/or B2O3 as a component to improve the refractoriness of inorganic fibres comprising SiO2, and CaO and/or MgO is described. The inorganic fibres have a composition such that SiO2 + P2O5-(58 + (if MgO > 10, 0.5 x (MgO-10) else 0)) > -2.4 wt.%.