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sAbstract: The Mg/Al laminated composites were fabricated by the accumulative roll bonding (ARB) at ambient temperature using the pure magnesium and commercial pure Al sheets. Mg grains were refined after the primary sandwich preparation and then homogenized during the following ARB process while the grain size of Al layer decreased with increasing of the accumulated strains. Both the yield strength and ultimate strength along rolling direction and transverse direction increased gradually while the elongation to failure along both directions decreased with increasing of the ARB cycles. Formation of the Mg17Al12 phase indicated that the ARB process at ambient temperature could lead to a metallurgic bonding of the Mg/Al interface. [Copyright &y& Elsevier]

Abstract: In the present study, 10vol.% SiCp/AZ91 magnesium matrix composites are fabricated by stir casting. The as-cast ingots are cut into cylindrical billets, and then forged at 420°C with different deformation amounts (40, 50, 60 and 80%) at a constant RAM speed of 15mm/s. The results illustrate that the addition of SiC particles has significant influence on refining grain size and improving tensile strength of AZ91 matrix, however, weakening basal plane texture. After forging SiCp/AZ91 composites, the intensity of basal plane texture increases as deformation amount increases. The grain size of composite matrix grows up slightly as the deformation amount increased to 60%, and then it was refined obviously as the deformation amount continues to increase to 80%. The smaller deformation amount is propitious to improve particle distribution, while lager deformation amount promotes SiC particle agglomeration. Thus, the tensile strength increases as the deformation amount increases to 50%, however, it decreases as the deformation amount continues to increase to 80%. [Copyright &y& Elsevier]

Abstract: SiCp/AZ91 magnesium matrix composite was fabricated by stir casting. The as-cast ingots were cut into cylindrical billets, and then forged at different temperatures (320, 370, 420, 470 and 520°C) at a constant RAM speed of 15mm/s with 50% reduction. The microstructure evolution of the composites during forging was investigated by optical microscope, scanning electron microscope, and transmission electron microscope. The texture of the forged composites was measured by neutron diffraction. Mechanical properties of the composite at different forging temperatures were tested by tensile tests at room temperature. It was found that a strong basal plane texture formed during forging, and the intensity of basal plane texture weakened as forging temperatures increased. The particle distribution in the composite was significantly improved by hot forging. Typical microstructures were obtained after forging at different temperatures and the composite with different microstructures offered different mechanical properties during tensile test. [Copyright &y& Elsevier]

The texture of the Mg/Al laminated composite fabricated by accumulative roll bonding was measured by neutron diffraction. The texture type of the Mg layer was typical rolling texture and the dominant texture of the Al layer was β-fiber rolling texture with scatter around the ideal orientations. The significant waviness structure caused by the shear band reduced both the intensity and the sharpness of the rolling texture of both Mg and Al layers. [Copyright &y& Elsevier]