Abstract: The present invention relates to pulverulent materials suitable for storing hydrogen, and more particularly to a method of preparing such a material, in which: (A) a composite metallic material having a specific granular structure is prepared by co-melting the following mixtures: a first metallic mixture (m1), which is an alloy (a1) of body-centred cubic crystal structure, based on titanium, vanadium, chromium and/or manganese, or a mixture of these metals in the proportions of the alloy (a1); and a second mixture (m2), which is an alloy (a2), comprising 38 to 42% zirconium, niobium, molybdenum, hafnium, tantalum and/or tungsten and 56 to 60 mol % of nickel and/or copper, or else a mixture of these metals in the proportions of the alloy (a2), with a mass ratio (m2)/(m1+m2) ranging from 0.1 wt % to 20 wt %; and (B) the composite metallic material thus obtained is hydrogenated, whereby the composite material is fragmented (hydrogen decrepitation).

Abstract: The invention relates to a method for preparation of a material adapted to reversible storage of hydrogen, including steps consisting of providing a first powder of a magnesium-based material, hydrogenating the first powder to convert at least part of the first powder into metal hydrides, mixing the first hydrogenating powder with a second powder additive, the proportion by mass of the second powder in the mix obtained being between 1% and 20% by mass, wherein the additive is formed from an alloy with a centred cubic structure based on titatnium, vanadium and at least one other metal chosen from chromium or manganese, and grinding the mix of first and second powders.

Abstract: A process for forming cast, magnesium based alloy articles having reduced microshrinkage comprising the steps of forming a molten alloy consisting essentially of magnesium together with 4 to 10% by weight aluminum, 0 to 1% by weight manganese, and either 0 to 3% by weight zinc or 0 to 1% by weight silicon, adding to the molten alloy 0.01 to 2% by weight strontium, and molding the molten alloy and solidifying to form a cast alloy article.

Abstract: The invention relates to a method and apparatus for sand molding composite articles formed of a light alloy metal and fibrous insert. A sand mold is formed containing a fibrous preform separated from the walls of the mold cavity. The mold is fed by means of a tube dipping into a liquid metallic bath therebelow. In the molding process, the pressure in the mold cavity and above the bath are reduced, and the pressure above the bath is increased to create a positive pressure differential .DELTA.P, thereby forcing molten metal from the bath into the mold cavity. The pressure in the mold cavity and above the bath are then increased to above atmospheric, and the pressure differential .DELTA.P is maintained until the metal in the mold cavity solidifies.

Abstract: The invention relates to an apparatus for pressure casting of metal parts which possibly contain fibres of ceramic material. The apparatus includes a cold chamber, and comprises a lower fixed plate 1, an upper movable plate 2, and a die 3 disposed between the upper plate and the lower plate, with the lower plate being provided with an injection means for liquid metal comprising an injection sleeve 5 having a piston 6 supported on a rod 7 slidable in the sleeve. The metal is contained in a sealed vessel connected to the injection sleeve by a conduit 9 by way of an orifice 8 in the sleeve, with a gas inlet in the vessel connected to a source of gas for selectively placing the liquid metal in the vessel under a gas pressure P2 which causes the flow of liquid metal in the conduit towards the sleeve.

Abstract: The invention relates to a process and an apparatus for improving the operation for low pressure casting of components such as aluminum and magnesium alloys by controlling the pressure of the inert gas used to cause the metal to flow downwards into the injection tube after the casting of a component at a value higher than that prevailing in the interior of the furnace, the difference between the two pressures being adjustable to a constant value, and enabling two different rates of flow of the inert gas to be established.

Abstract: A new crucible for use in the thermal analysis of metal alloys and especially aluminum alloys into which a thermocouple may be placed into a metallic thin-walled sheath which is secured in and extends upwardly from the crucible base and is connected to recording apparatus. The crucible is formed of an extremely thin-walled metallic cylindrical envelope having a base and a cake of heat-insulating material resting inside the envelope on the base, the thermocouple sheath extending upwardly through said cake.