Kryvoruchko D. Scientific backgrounds of machining simulation using numeric methods

Object of study: machining operations with metal cutting tools. Objective: working out of scientific bases of thermomechanical models creation of machining operations for development at designing of effective tools and parameters manufacturing process based on mechanical tests of workpiece material and its orthogonal cutting. Research methods and equipment: For prediction of type, form and sizes of the chip, stress, strain and thermal fields in a zone cutting and a deformation component of friction forces a finite element method (FE) is used in this study. Data acquisition about thermomechanical properties of work materials are performed by means of tension (GOST 1497-84, GOST 9651-84) and compression (GOST 25.503-97) tests with standard and special samples at the normal and high temperatures, and also orthogonal cutting. Measurement of an adhesive component of friction forces is performed by indentation of the spherical rotating indenter in a half space at normal temperature. Theoretical and practical results: in this study scientific bases of construction 2D - and 3 D-FE predictive models of machining operations are developed, the scientific and technical problem of machining efficiency increasing by predicting of parameters of machining operation without conducting of experimental researches of directly cutting in conditions which are investigated is solved. Novelty: the new concept of prediction of parameters of machining operation in the set conditions; it is proved by modelling a hypothesis about direct dependence between a deformation component of external friction force and the fundamental characteristic of the is deformation conditions of a chip contact layer: the relation of the real pressure to an average yield stress; fracture and friction models are developed for metal cutting and possibility of chip prediction without conducting of preliminary experiments on cutting is proved. Degree of implementation: Results of research are used on VAT "Sumy НВО of M.V.Frunze" (Sumy) for decrease preparation time of manufacture, by AT "ROTOR" (Sumy), Company "Nasostechkomplekt" (Sumy) for improvement of quality and productivity of machining of the compressor equipment parts, in Institute of superhard materials NAS of Ukraine (Kiev), Physicotechnical institute NAS of Belarus (Minsk), Institute of machine tools of University of Stuttgart (Germany) for an intensification of researches of machining operations. Scope of application: metal cutting tool industry.