Prediction of earing of aluminium sheets from {h00} pole figures

Abstract

Earing of deep drawn cups is a result of non-uniform formability caused by crystallographic anisotropy. The prediction of earing is of interest since the rise of the rolling process. Today's prediction methods are based on theoretical material behaviour functions and apply only within a certain sheet geometry range. In this manuscript, a new and simple method is presented which can be used to calculate the earing of aluminium sheets showing four-fold earing if only texture data is available. The method was applied on 0.3 and 3 mm thick cold rolled 1050 type aluminium sheets subjected to annealing heat treatments for different time intervals to promote recrystallization processes and obtain different earing behaviour. Predicted cup heights are validated with measured data obtained from the performed deep drawn tests. Average earing is also predicted and validated. It is shown that the proposed method is able to predict the type and magnitude of earing with satisfactory results for both 0.3 and 3 mm sheet thicknesses.