Strain path effects under hot working: an introduction

Material models are often required to facilitate the development of new pro ducts. This is particularly true of hot rolled products, especially shaped sections. Most material models assume that the material behaviour can be de scribed with reference to strain rate, temperature and an equivalent plasti c strain. The use of the last variable implies that. the "strain path" does not significantly influence material behaviour. Evidence suggests that thi s assumption is invalid and that the accuracy of future material models wil l be enhanced if strain path effects are taken into consideration. The impo rtance of strain path effects under hot working conditions, is being invest igated. The review discusses previous investigations on strain path effects , mainly carried out under cold working conditions. The conclusions from th e review of this work is intended to determine frame of reference within wh ich future test data and microscopic analysis can be assessed. The review a lso discusses the elementary basis of continuum plasticity models and their potential for describing strain path effects. (C) 2000 Elsevier Science S. A. All rights reserved.