An Investigation of the Effects of Cold Rolling and Annealing on the Corrosion and Tensile Behaviors of Al/Steel Multilayer Composite

Abstract

In this study, Al/Steel multilayer composite was produced by accumulative roll bonding (ARB) process using Al-1100 and St-12 strips. Microstructure, mechanical properties and corrosion behavior of the composite were studied by scanning electron microscopy (SEM), tensile test, Vickers microhardness tests, cyclic polarization and electrochemical impedance spectroscopy (EIS) measurement in 3.5 wt% NaCl solution. After one ARB cycle (2 roll-bonding cycles), the multilayer composite of 4 layers of Al and 2 layers of steel was produced. The tensile strength of the Al/steel multilayer composite reached 390.57 MPa after the first ARB cycle, which was 1.29 times larger than that of the starting steel while composite density was almost half the density of the steel. Corrosion behavior of the composite revealed a considerable improvement in the main electrochemical parameters, as a result of enhancing influence of cold rolling. The results indicated that strength and corrosion resistance of Al/steel composite generally decreases and elongation increases after annealing.

Keywords

• accumulative roll bonding (arb)
• multilayer composite
• mechanical properties
• corrosion behavior.