A study on material flow in isothermal extrusion by FEM simulation

Authors: Peng, Z. and Sheppard, T.

Journal: Modelling and Simulation in Materials Science and Engineering

Volume: 12

Issue: 5

Pages: 745-763

ISSN: 0965-0393

DOI: 10.1088/0965-0393/12/5/001

Abstract:

Numerous methods have been suggested or are being used to employ isothermal extrusion operation in commercial presses. The most popular methods may be broadly divided into two types: setting up a longitudinal thermal gradient in the billet or controlling the extrudate exit temperature by varying the ram speed. If the velocity gradient varies it could cause the extrusion to bend or twist, creating residual stress, and the same is true for variation in temperature. So, it is relevant to understand how the material flows through the die and ascertain how the flow pattern in isothermal extrusion differs from the normal extrusion process. In this study, with the help of previous experiments and finite element method (FEM) simulations, isothermal extrusion by two differing methodologies are investigated and discussed: the material flow pattern and the extrudate surface formation in isothermal extrusion. The extrusion force, the exit temperature, the temperature distribution in the transverse direction of the extrudate, the pressure on the tooling, the strain and strain rate distribution are also discussed to assist in the evaluation of isothermal extrusion.

Source: Scopus

Preferred by: Terry Sheppard