Investigation on bonding strength of steel/aluminum clad sheet processed by horizontal twin-roll casting, annealing and cold rolling

• Published in: Materials & design Vol. 112; pp. 263 - 274
• Main Authors: Chen, G., Li, J.T., Yu, H.L., Su, L.H., Xu, G.M., Pan, J.S., You, T., Zhang, G., Sun, K.M., He, L.Z.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 15.12.2016
• Subjects: Aluminum; Annealing; Bonding strength; Clad sheet; Cold rolling; Horizontal twin-roll casting; Peel strength; Reduction; Sheet metal; Sheets; Cold rolling; Clad sheet; Annealing; Peel strength; Horizontal twin-roll casting
• ISSN: 0264-1275; 1873-4197
• DOI: 10.1016/j.matdes.2016.09.061

In this work, a stainless steel/aluminum clad sheet was produced successfully by horizontal twin-roll casting. The interface morphology, element distribution and bonding strength of the clad sheets after different annealing and cold rolling processes were investigated using optical microscopy, electron probe micro-analyzer and T-type peel test. The surfaces of the steel and aluminum sheets after peeling were studied using scanning electron microscopy. In the as-cast clad sheet, a 3μm thick diffusional layer exists at the Fe/Al interface. The average peel strength is 12N/mm. Suitable annealing treatment can greatly improve the bonding quality of the interface. The average peel strength increases with increasing annealing temperature, from 12N/mm at 450°C to 21N/mm at 510°C. After annealing at 540°C, the diffusional layer becomes almost three times the original thickness, which results in a sharp drop in the average peel strength to 5N/mm. Cold rolling processing also improves the bonding strength of the clad sheets. The average peel strength of the clad sheet annealed at 510°C increases as the reduction in thickness by cold rolling increases, from 23N/mm for 25% reduction, to 28N/mm for 40% reduction. [Display omitted] •A stainless steel/aluminum clad sheet was produced successfully using horizontal twin-roll casting technique.•Further annealing can increase the bonding strength by eliminating residual voids and increasing salient at the interface.•Further cold rolling can also increase the bonding strength by forming wavelike interface.