Finite-Element Modelling of Forging with Torsion: Investigation of Heat Effect

Abstract

The modern trend in material forming is the application of the combined processes for forging. Forging with torsion (FWT) is a non-conventional combined forging technology which is a sequential combination of two processes – the upsetting (axisymmetric compression) and the torsion (pure shear). The FWT is a relatively new forging process, preferably used for manufacturing the axisymmetric parts like disk or flange made of either continuous (bulk, casted or extruded) either discrete (powders and chips after machining) or additively manufactured parts. There are no limitations on the type of the materials treated by means of FWT. Some examples of worth-studying aspects in FWT are as follows: (1) the effect of the roughness on the material flow on tool-workpiece interface, (2) the effect of the severe plastic deformation on the microstructure of the obtained part, and (3) the effect of heat on material flow, especially the material flow on tool-workpiece interface. This article focuses on the investigation of the heat effect in FWT based on a finite-element simulation by QFORM-3D. The results presented in the article demonstrate the first approach to understand properly the phenomenon at the tool-workpiece interface. It is assumed that the heat effect could be decomposed, at least, into two components, viz., the heat effect of plastic deformation of a workpiece and that due to the contact friction on a tool-workpiece interface. The developed finite-element model allows to investigate the effect of friction factor on the temperature of the material within the deformation zone as well as at the tool-workpiece interface for different values of the angular speed of a rotating tool.