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The influence laws of two different rolling processes on the microstructures and properties of 6016 aluminum alloys in rolling, T4, T4P states, and aging are studied, respectively. The microstructures under different rolling processes are also analyzed by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM) and electron backscatter diffraction (EBSD). The results indicate that during the cold rolling process, compared with B alloy, A alloy generated small initial grains. The small initial grains will increase the deformation resistance, and the strength and hardness of A alloy are better after rolling, but with poor plasticity. After solution treatment, A alloy generated small grains with recrystallization, the hardness, plasticity, and formability of A alloy in T4 state are better than B alloy after solution treatment and natural aging. A alloy is more sensitive to aging response, and artificial aging occurs during the pre-aging process. The proportion of large Angle grain boundaries in A alloy is large but with small dislocation density, uneven distribution, and small texture content. This makes A alloy have better strength and hardness in T4P and poor plasticity and formability than B alloy after solution treatment, pre-aging and natural aging. However, the strength and hardness of A alloy are also smaller than that of alloy B after artificial aging. [ABSTRACT FROM AUTHOR]

The poor interface bonding between graphene and copper matrix significantly impair the strengthening effect of graphene, but it can be improved by graphene modification. In this work, the Ni-rGO compound powders were synthesized via hydrothermal method, and the Cu matrix bulk composites reinforced by Ni-rGO and rGO were prepared by the molecular-level mixing method along with spark plasma sintering, respectively. The sintered bulk materials were examined by transmission electron microscope, scanning electron microscope, Raman spectroscope and X-ray diffractometer, and the mechanical and electrical properties were tested as well. The results indicated that the incorporation of Ni-rGO exhibits a more obvious strengthening effect. As compared to the 0.1wt.%rGO/Cu composite material, the yield strength, tensile strength and elongation of the 0.1wt.%Ni-rGO/Cu composite material are increased by 10.9, 13.5 and 23.9%, respectively. This can be ascribed to the modified structure of graphene along with the improved interface bonding by the incorporation of Ni nanoparticles in rGO. [ABSTRACT FROM AUTHOR]