TMP as an Effective Technique to Produce Ultra-Fine Grained Steels

Abstract

In recent years, great attention is paid to the creation of methods andthe technological processes providing ultrafine-grained state of metal materials including submicro - and nanocrystalline ones. It pertains to structural components and to the phases constituting the particular metal or alloy. The main development in terms of obtaining bulk metallic materials received in recent years, various schemes of processing of metals by plastic deformation, which allows to realize the so-called severe plastic deformation (SPD). Such approach usually propose realization of large plastic strains, providing a well-developed fragmented substructure with the creation of high angle misorientation of the boundaries between the fragments of the substructure. The second direction in receiving finely divided state is to create technologies that provide a significant refinement of phase as a result of processing. The most effective way of achieving both the above effects applied to bulk metallic materials is Thermomechanical Processing (TMP), which can be used as a standalone technology or in combination of such methods as accumulation roll bonding (ARB) or other similar SPD methods. This paper discusses various methods of thermomechanical processing, based on the use of hot, warm and cold deformation, in various combinations applied to single and multiphase steels, ensuring the achievement of ultra-fine grained structure with elements of submicro - and nanostructures.