Production of Al/Sn multilayer composite by accumulative roll bonding (ARB): A study of microstructure and mechanical properties

In this research, the Al/Sn composites, a part of the plain bearing components, were produced by the accumulative roll bonding (ARB) up to eight cycles. By increasing the number of ARB cycles, the layered structure became unstable. The deformation of two constituent metals was almost uniform until the second ARB cycle. The obvious necking, wavy appearance and rupture of the Al layers were observed after the third ARB cycle. The final microstructure consists of a uniform distribution of the hard Al phase within the soft Sn matrix. The maximum tensile strength reached 155 MPa after two cycles, which was around 2.2 times higher than that of the pure Al; thereafter, it decreased until the fourth cycle and then increased until the last cycle. The tensile elongation of the produced composites decreased to about 3% and remained approximately constant until the last cycle. The hardness of the individual layers increased gradually by increasing the number of ARB cycle. The tensile fracture surfaces revealed dimples in both Al and Sn after the first-to eighth ARB cycles. The XRD results showed that no new phase has been formed during ARB.