Wire fracture during processing causes important losses for the drawing industry. A lot of failure criteria have been developed in recent years in order to predict and avoid this problem. Nevertheless, their success is limited up to now. One of the reasons may be that in these models the mechanical behaviour of the material is represented only by the stress-strain curve obtained in conventional tensile tests (low strain rate). However, in modern industrial processes, drawing speeds can reach values of 10-100 m/s, which produces strain rates of 10{sup}3 s{sup}(-1) or even 10{sup}4 s{sup}(-1). The aim of this work is to study the strain rate 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) have been performed. The experimental stress-strain curves have been used to implement a numerical 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 flow in modern drawing processes. If this effect is not taken into account, the calculated values for the drawing force, the friction coefficient and the stress and strain fields may be not reliable, leading to wrong failure predictions.
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机译：加工过程中的电线骨折会导致绘图行业的重要损失。近年来近年来开发了大量的故障标准，以预测和避免这个问题。然而，他们的成功仅限于现在。其中一个原因可以是，在这些模型中，材料的力学行为仅由常规拉伸试验中获得的应力 - 应变曲线（低应变率）表示。然而，在现代工业过程中，绘制速度可以达到10-100米/秒的值，其产生10 {sup} 3 s {sup}（ - 1）甚至10 {sup} 4 s {sup}的应变速率-1）。这项工作的目的是研究对铁素体钢丝的力学行为的应变速率影响。为此目的，已经进行了常规拉伸试验（低应变率）和霍普金森棒试验（高应变率）。实验应力 - 应变曲线已被用于实施绘图过程的数值模型，以考虑应变率效应。数值结果表明，应变率对现代绘图过程中的材料流具有显着影响。如果没有考虑这种效果，则绘制力的计算值，摩擦系数和应力和应变场可能不可靠，导致错误的失败预测。
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