Machining accuracy improving based on joint numerical geometric and physical modeling.

Abstract

Motivation for the new study. Technological preparation of modern mechanical engineering production is based on CAD/CAM/CAE/CAPP systems. In CAD/CAM systems, modeling of
parts and machining on CNC machines is performed in an ideal setting: smooth surfaces, linear edges and point vertices of bodies are used; elastic and thermal deformations and tool wear are not taken into account. As a result, parts obtained by modeling often differ from those obtained in the machining process. Modern scientific studies provide numerical calculations of the stress-strain state of idealized tools and workpieces, including modeling of the cutting zone, as well as consideration of their deformations
in control programs for CNC machines. At the same time there are analytical solid models of tool wear surfaces and their use in chip formation models. However, all these studies are reflected in publications separately, and the specified idealized models reduce the adequacy of calculations. There is a need for
CAD/CAM/CAE modeling in view of roughness, wear, deformations of the elements of the technological system and their joint consideration for calculating the machining accuracy during CNC machining.
Thus, the aim of the new study is to improve the machining accuracy during CNC machining by joint numerical geometric and physical modeling of such processing in view of roughness, wear and deformations of the elements of the technological system. The methodological base of the study includes voxel modeling in conjunction with mesh or meshless methods for calculating the stress-strain state of the technological system elements. Obtained and expected research results: mathematical models of
the main types roughness with peaks located along specified lines, mathematical models of the main types of tool wear, voxel modeling of the technological system elements, including modeling of dispersed and fiber-reinforced 3D woven composite workpieces, mathematical models of tool geometry
changing caused by tool wear during machining and the effects of this wear, as well as deformations on the machined parts. It is planned to develop numerical modeling of machining fiber-reinforced composite workpieces to determine the cutting forces. General conclusions are related to the assessment of the
prospects of the proposed numerical approach in the new generation of CAD/CAM/CAE systems and the potential of their application in pre-production engineering.