Rapid crystallization is a well-known method for production of ultrafine-grained metallic materials using the overcooling effect. Unfortunately, this method provides material in dispersed form with very limited dimensions of individual particles, which must be consolidated to bulk form for engineering use. To prevent destabilization of ultrafine-grain structure of polycrystalline particles the consolidation process should to be quick enough and must be conducted at reasonably low temperatures. Such reasons suggest the process of plastic consolidation. In this process plastic deformation of individual particles develops new surfaces in status nascendi, which is able to create strong bonds between collectively deformed particles of dispersed materials and converts the powder to the bulk form. The plastic consolidation by isothermal extrusion is the agglomeration process of plastically deformable particles without involving diffusion effects. Bulk materials with no measurable porosity are the product of this process, in which the character of interaction among individual particles of powder shows similar character to interaction at grain boundaries in polycrystalline metals. (C) 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
