Zhbankov I. Development of Scientific Basics of Hot Forging Processes and Improvement of the Technological Process of Heavy Forgings Manufacturing

Object of research - technological processes and press tools for manufacturing heavy forgings. Research purpose - increasing technical and economic parameters of the technological processes of forging large forgings based on the development of scientific bases of processes of hot plastic deformation and improvement of technological methods and regimes of forging. Research methods are a finite element method, method of grids, strain measurement, measurement of mechanical properties, macro- and microstructure studies, experiment planning and mathematical statistics. Theoretical and practical results are determined the influence of hot plastic deformation on microstructure and mechanical properties of product produced by open die forging; for computation of open die forging processes there were used the models which allow prognostication of microstructure evolution during hot plastic deformation; the method of plasticity recovery calculation during hot multistage forging was improved; the method of calculation of metal flow curves was improved with the usage of standard mechanical data of material such as yield and peak stress. Novelty - on the basis of an assessment of the evolution of the metal microstructure were obtained fields of the grain size distribution in the billets which are produced by new forging schemes; improved method for deformability estimation in the technological processes of multi stage hot plastic deformation; improved the model of hot plastic deformation, which is described by the analytical dependence and allows the calculation of changes in metal flow stress under the influence of temperature and strain rate and is based on the use and synthesis of standard mechanical characteristics of the metal. The degree of implementation - new technological processes and forging press tools, thermo mechanical deformation modes are implemented. Scope of use are enterprise heavy and power engineering, industrial research institutes.