Determination of friction coefficient encountered in large deformation processes

Sofuoglu H., Gedikli H.

TRIBOLOGY INTERNATIONAL, vol.35, no.1, pp.27-34, 2002 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 35 Issue: 1
  • Publication Date: 2002
  • Doi Number: 10.1016/s0301-679x(01)00076-7
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.27-34
  • Keywords: coefficient of friction, friction calibration curves, metal forming processes
  • Karadeniz Technical University Affiliated: Yes


A new technique, namely, the open-die backward extrusion test technique, was developed as an alternative method to the ring compression test in order to quantitatively evaluate the coefficient of friction, mu, at the die/workpiece interface. This technique relates the percentage deformation in height of the specimen to the percentage increase in extruded height of the specimen. In this study, the open-die backward extrusion tests (ODBET) were simulated for different aspect ratios, (HID), and different die geometries, (d/D), by utilizing an elastic-plastic finite element code (ANSYS) in order to obtain the friction calibration curves (FCCs). The results indicated that the extruded height is related to the friction conditions at the die/workpiece interface. Therefore, ODBET can be used to generate FCCs to determine the coefficient of friction at the die/workpiece interface in large deformation processes. (C) 2002 Elsevier Science Ltd. All rights reserved.