Laminated steel/aluminum composites: Improvement of mechanical properties by annealing treatment

Lightweight, high-strength structural materials are among the most common materials requested by steel producing companies. In this study, a lightweight, laminated carbon steel/6061 aluminum composite was designed and manufactured using the facile process of cold roll bonding. Using various annealing treatments, changes in the interfacial microstructure, mechanical properties, strain partitioning, and bonding strength of incorporated layers, were investigated. Among different CRB sheets produced by st-37 steel and 6061 aluminum alloy through a thickness reduction of 65%, optimal tensile strength (619 MPa) and ductility (16.1% elongation) were obtained for the sample annealed at 400 degrees C for 90 min; the strength-to-weight ratio was 96.7, and the density was measured to be 6.4 g/cm(3). The results indicated an increase in strength-to-weight ratio by 22%, and a decrease in density by 18% as compared to the commercial low-carbon steel.