Effect of the local friction and contact nature on the Built-Up Edge formation process in machining ductile metals

摘要

The BUE can affect the tool wear and surface integrity when machining ductile metals. The main goal of the present work is to investigate the close link between the BUE formation and the tribological behaviour at the tool-workmaterial interface when machining ductile metals. Machining AA2024-T351 aluminium alloy with cemented carbide tool WC-Co is considered as a case study. A new method based on the contact conditions variation (i.e. introduction of a time-dependent friction coefficient) at the tool-workmaterial interface is proposed to predict the BUE formation in the frame of a finite element (FE) modelling. A 2D ALE-FE model of orthogonal cutting has been developed for this purpose. Two cases have been considered, which correspond respectively to an abrupt change and a gradual evolution of the friction at the tool-workmaterial interface. Results are discussed based on the effects of the friction change on predicted thermomechanical fields at the cutting zone. (C) 2015 Elsevier Ltd. All rights reserved.