Improvement of bonding strength of horizontal twin-roll cast steel/aluminum clad sheet by electromagnetic fields
Electromagnetic field is an available online method to increase bonding strength of clad sheet manufactured by horizontal twin-roll casting (HTRC). In this paper, an electric current pulse (ECP) and a complex field (static magnetic field (SMF) together with ECP) are exerted during HTRC of steel/aluminum clad sheet. The produced clad sheet has good appearance, and no visible defects exist at the bonding interface. The inter-diffusion zone at Fe/Al interface in ECP and SMF+ECP sheets is 3 and 4 μm, respectively, and the latter increases slightly compared with that in non-field sheet. The average peel strengths (APS) of ECP and SMF+ECP sheet are 14 and 21 N/mm, respectively, which increase by 2 and 9 N/mm compared with 12 N/mm of non-field sheet. The APS increment in SMF+ECP sheet is resulted from the increment of interface bonding spots and the enhancement of inter-diffusion zone width.