Microstructure Characteristics and Corrugation Interface Behavior of Al/Mg/Al Composite Plate Rolled Under Large Strain

Traditional rolled (TR) aluminum (Al)/magnesium (Mg)/aluminum (Al) composite plates have many bottlenecks such as multiple passes, low interlaminar strength, and weak mechanical properties. In this paper, the hard-plate rolling (HPR) method was used to prepare Al/Mg/Al composite plates under a single pass reduction of 60%. The results show that the ultimate tensile strength (UTS) of the composite plate obtained by hard-plate rolling is 262.3 MPa, and the percentage of total elongation at fracture (A_t) is 12.3%, which is 31.6% and 37.4% higher than that of the traditional rolling, respectively. It is attributed to the unique corrugated interlocking structure of the interface of the composite plate caused by hard-plate rolling. The shear texture produced by the Mg plate weakens the strong-basal texture. At the same time, the strong basal slip and the large amount of energy stored in the deformed grains provide favorable conditions for dynamic recrystallized (DRX) nucleation. The microstructure is deeply refined by DRX, and the strength and plasticity of the composite plate are improved synchronously. It provides scientific guidance for the development of high-performance lightweight composite plates and the research on hard-plate rolling technology and also has good industrial production and application potential.