Abstract: A tubular composite element of metal, particularly steel, whereby at least the two opposite ends of the tubular composite element consist of different materials, for example carbon steel and stainless steel, and a process and a pressing for simultaneously producing two or more of such composite elements, at least two powders each consisting of one of the different materials, which have been produced by atomizing melts of the materials in question, are introduced alternately and separately from one another into three or more sections each extending over a predetermined axial length of a metallic hollow cylindrical casing and are condensed by vibration and/or ultrasound to around 60 to 70% of the theoretical density and by cold isostatic pressing of the closed casing under a pressure of at least about 3000 bars to at least 80% of the theoretical density and the pressing thus obtained is heated, subsequently hot-extruded to form a tube and the tube thus formed is divided up into the two or more composite element

Abstract: This invention relates to a process and an apparatus for converting lump-size material, particularly scrap, of titanium metal or its alloys, preferably of low oxygen content, into powder-form material, which is useable for forming in a powder-metallurgical way pressings and workpieces, wherein the lump-size material is highly embrittled by charging with hydrogen, the embrittled material is size-reduced by means of size-reducing machines, particularly impeller breakers, impact mills, hammer mills, impact hammer mills or hammer breakers, the size-reduced brittle material preferably having a particle size of less than about 10 mm and more particularly of less than about 6 mm is further size-reduced by means of at least one jet stream by impinging on a baffle plate or an anvil or on the particles of at least one other jet stream for the purpose of conversion into the powder-form material, and the powder-form material is converted into the ductile state by heating, preferably at temperatures above 450.degree. C.