Analysis of warping during flat rolling of bimetallic slabs

Abstract

The current study analyzes the warping behavior of bimetallic slabs during the flat rolling process. An analytical model that predicts the degree of warping during the rolling of bimetallic slabs is developed, based on differential bending, which occurs due to the mismatch in longitudinal elongation. The warping model focuses on the mismatch of the lengthwise elongation, due to differences in the deformation resistances of constituent materials in the bimetallic slab. With this analytical model, warping can be predicted for various processing parameters, such as initial thickness ratios and rolling reductions. To validate the model, flat rolling experiments using Al1050/Al6061 bimetallic slabs, produced by continuous clad casting, were conducted. The deformation characteristics of the bimetallic slabs during rolling were also assessed by a finite element analysis using the commercial code, FORGE™. The results from the current study show that the warping behavior of bimetallic slabs during flat rolling can be characterized with a high degree of reliability.