Computational Analysis of Thermo-Mechanical Fields in Hot Roll Bonding of Aluminum Validated by Experiments

Roll bonding is extensively used in various industries for obtaining engineering components comprising several metallic layers. The load-bearing ability of such components strongly depends on the interface bonding strength between these layers. Nevertheless, the relation between the thermo-mechanical fields that develop at the interface during rolling and the resulting bonding strength is still not clearly defined. The current study presents a coupled thermo-mechanical computational investigation of a hot roll bonding process of aluminum plates validated by experiments. A novel experimental rolling configuration proposed in this study enables evaluating the interface strength by subsequent three-point bending tests. The rolling models were used for analyzing the time-dependent thermo-mechanical fields that develop at the interface for different reduction ratios. It is demonstrated that a 2D FE representation is not sufficient to accurately describe the interface conditions and a 3D analysis must be used. The computed fields in the deformation zone examined the bonding strength using a previously published bonding strength criterion for solid state bonding in bridge die extrusion.