Digital Repository, ECF14, Cracow 2002

Font Size: 
The Effect of Strain Rate on Steel Wires Failure During Cold Drawing

Last modified: 2013-02-10


Wire fracture during processing causes important losses for the drawingindustry. A lot of failure criteria have been developed in recent years in order to predict andavoid this problem. Nevertheless, their success is limited up to now. One of the reasonsmay be that in these models the mechanical behaviour of the material is represented only bythe stress-strain curve obtained in conventional tensile tests (low strain rate). However, inmodern industrial processes, drawing speeds can reach values of 10-100 m/s, whichproduces strain rates of 103 s-1 or even 104 s-1. The aim of this work is to study the strainrate effect on the mechanical behaviour of a ferritic steel wire. For that purpose,conventional tensile tests (low strain rate) and Hopkinson bar tests (high strain rate) havebeen performed. The experimental stress-strain curves have been used to implement anumerical model of the drawing process taking into account the strain rate effect.Numerical results show that the strain rate has a remarkable influence on the material flowin modern drawing processes. If this effect is not taken into account, the calculated valuesfor the drawing force, the friction coefficient and the stress and strain fields may be notreliable, leading to wrong failure predictions.

Full Text: PDF