Abstract: An asymmetric or double-sided porous material, which comprises at least one porous layer of a polymer on a porous support or carrier, where the polymer is formed from a self-assembled microstructured liquid. A method of producing the same comprising positioning the support or carrier against or adjacent an inert surface, providing an excess of polymerisable liquid to completely wet the carrier and form a film through capillary action between the carrier and the inert surface and penetrating the carrier, then polymerising the liquid.

Abstract: A nitride of a metal or solid metalloid is produced by ball milling a powder of a metal or metalloid in a nitrogen, or nitrogen-containing atmosphere (such as ammonia). The pressure in the ball mill is normally from 100 to 5,000 kPa, typically about 300 kPa. The ball mill temperature may be from room temperature to 500.degree. C., preferably from 200.degree. C. to 400.degree. C. The product powder is normally pressure moulded and annealed at 800.degree. C. for about 1 hour to produce a strong, hard body. Controlling the degree of nitration, or mixing the product nitride powder with a metal powder before pressure moulding, enables a composite comprising a metal matrix with a dispersed nitride phase to be produced. An alternative technique, involves ball milling the metal or metalloid powder with an organic nitrogen-containing chemical which dissociates in the ball mill. This yields a mixture of the nitride and carbide of a metal or solid metalloid.

Abstract: A ball mill for use in mechanical alloying and grinding comprising a plurality of ferromagnetic balls within a spherical or cylindrical chamber or cell of a paramagnetic material. The chamber has a substantially horizontal axis of rotation. At least one magnet is mounted outside the chamber to produce a magnetic field within the chamber. The magnet is physically moveable, relative to the chamber, between a plurality of locations on an arc centered on the axis of rotation of the chamber.

Abstract: Metal carbides may be formed by mixing metal powder with a stoichiometric amount of graphite, compressing the same in a mould/die and then sintering. High temperatures (and maybe a bonding agent) are required to effect the final step and finished product. These disadvantages are overcome by exploiting dry high energy milling to bring the starting materials into a very finely divided and reactive state, with regions of metal, carbon and metal based solid solution ranging from 3 to 100 nanometers in diameter. As an alternative source of carbon, cationic organic surfactants may be used instead of graphite in the appropriate proportion. Compacting the milled mixture, followed by sintering at lower temperatures by a margin of at least 400.degree. C., will produce very strong dense carbides at low cost. The method may be extended to include metal based composites, which also includes cermets, by incorporating an appropriate excess of metal powder(s) in the starting materials.