Abstract: A process for producing a metallic tool, mould, die or other body of significant thickness or a coating, the process comprising directing a spray (3, 4) comprising molten metallic droplets carried by a propelling gas toward an object surface (7) of a substrate or pattern (5) so as to build up a metallic deposit or coating comprising the mould, tool, die, body or coating on the object surface (7) of the substrate or pattern (5), wherein at one or more predetermined stages during spraying droplets of a relatively large mean size are sprayed and at one or more other stages droplets or a relatively smaller mean size are sprayed.

Abstract: A facsimile of article to be produced by tooling is laid in register with a first tooling part and sprayed metallic material is deposited over the first tooling part and the facsimile of the article in order to form a second tooling part. The first tooling part typically comprises a metallic material and portions of the first and second tooling parts bounding the article facsimile are typically in metal to metal contact with one another. The tooling parts are separated and the article facsimile removed.

Abstract: Porous regions or void regions of spray deposited articles of one composition are infilled with molten material of a differing composition which subsequently solidifies. The molten material flows to infill the porous or void regions under the influence of applied pressure or capillary type action. Typically, the sprayed material is molten metallic material, and the void porosity filling material is also metallic in composition but having a lower melting point.

Abstract: Atomized metal is deposited metal onto a substrate so as to cause at least partial solidification of the deposited metal; further atomized metal is deposited onto the partially solidified deposited metal on the substrate; and the metal deposited onto the partially solidified deposited metal is allowed to fully solidify on the substrate; the cooling of the further deposited metal, and the composition of the metal and/or of a gas used in the atomization of the further atomized metal being tailored such that volumetric contraction on solidification and cooling of the further deposited metal is compensated for, when the deposited metal has been cooled to ambient temperature, by volumetric expansion in a reaction or phase change in the further deposited metal.

Abstract: Metallic articles having heat transfer channels are produced by solidification of molten metallic material about pre-formed channel defining members such that a solidified metallic deposit having heat transfer channels is formed. The channel defining members may be in the form of either solid elements (which are subsequently removed to leave the channels), or conduit elements (which may remain permanently embedded in the article). Moulds, dies, cores and other tools for use in moulding or casting of plastics and metals are particularly suitably formed by the process, the heat transfer channels being used for cooling of the respective articles during use. The molten metallic material is preferably deposited by spray forming utilizing one or more sprays of molten metallic material.