Evaluation of Critical Interfacial Friction in Cross Wedge Rolling

Abstract

For the purpose of characterizing excess initial slip, the critical value of interfacial friction in the cross wedge rolling (CWR) process is investigated. After describing CWR and its failure mechanisms, an analytical method is presented for determining the critical friction condition in a cross wedge rolling process. Using specialized pin-on-disk experiments, a technique is then introduced for determining the actual friction coefficient in a CWR operation. By comparing the critical and experimental friction coefficient values, a procedure for predicting the likelihood of excess interfacial slip failure in cross wedge rolling is established. The validity of such a procedure is subsequently ascertained for a specific set of operating conditions using the finite element method and CWR prototype experiments.