REVIEW OF STRUCTURAL STEEL PROGRAMMING OF THERMO-MECHANICAL PROCESSING METHOD Abu Afealiokhe Lukman Department Mechanical Engineering, Delta State Polytechnic, Ogwashi Uku, Delta State, Nigeria

Abstract

This paper discusses the technology that allows to obtain high-strength products made of structural carbon and alloy steels with hardening processing named the technology of programmed thermo-mechanical processing (PTMP). Targeted material structure research of hot deformation processing makes possible creation of new important technologies of thermo-mechanical processing (TMP). The programmed thermo-mechanical processing objective is to intense growing process of imperfections during thermal processing and plastic deformation of crystalline lattice, which improves structural conditions and mechanical properties of the product. The desired results achieved only by full realignment of the crystal lattice and micro-grain structures, caused by combined mechanical and thermal processing. Therefore, the objective of the programmed thermo-mechanical processing is to combine two technologies: thermal- and mechanical- processing, into a single production process that allows obtaining of rational micro-grain structural conditions of alloy and the appropriate density of crystalline lattice imperfections that increase forges mechanical properties. To achieve fine alloy structure on various levels (sub-, macro- and micro-grain) PTMP technology must provide regulation of deformation intensity and thermal impact to forged material with programmed manufacturing working algorithm. Designed technology aimed to form a crystalline lattice with desired properties, and fixed chemical composition. The combined mechanical and thermal effect, not only leading to a high density of crystalline structure imperfections but also the most importantly provides homogenous recrystallization process throughout the volume of a workpiece, which provides significantly increased mechanical properties of forgings processed by PTMP.