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As the applications of heterogeneous materials expand, aluminum laminates of similar materials have attracted much attention due to their greater bonding strength and easier recycling. In this work, an alloy design strategy was developed based on accumulative roll bonding (ARB) to produce laminates from similar materials. Twin roll casting (TRC) sheets of the same composition but different cooling rates were used as the starting materials, and they were roll bonded up to three cycles at varying temperatures. EBSD showed that the two TRC sheets deformed in distinct ways during ARB processes at 300 °C. Major recrystallizations were significant after the first cycle on the thin sheet and after the third cycle on the thick sheet. The sheets were subject to subsequent aging for better mechanical properties. TEM observations showed that the size and distribution of nano-precipitations were different between the two sheet sides. These nano-precipitations were found to significantly promote precipitation strengthening, and such a promotive effect was referred to as hetero-deformation induced (HDI) strengthening. Our work provides a new promising method to prepare laminated heterogeneous materials with similar alloy TRC sheets.

In this paper, the effects of size, morphology and distribution of eutectic silicon on the thermal conductivity of Al-8Si alloy modified by Sr (0.04, 0.08, 0.12 wt.%) and Sb (0.1, 0.3, 0.5 wt.%) elements with T6 heat treatment were investigated. The results show that the modified fibrous eutectic silicon has a significant capability of improvement of thermal conductivity, while the amount of the modifier has a relatively weak effect on thermal conductivity. After T6 treatment, the fracture or spheroidization of the flake eutectic silicon and the disappearance of clustering phenomenon could raise thermal conductivity, but the coarsening of fibrous eutectic silicon is inconducive to thermal conductivity. Finally, the effect of eutectic silicon on electron transport is analyzed in detail, which could provide a reference for enhancing the thermal (or electrical) conductivity of hypoeutectic Al-Si alloy through effective microstructure control.

Three-dimensional (3D) sandwich composites are an excellent material, boasting light weight, high strength, and high specific stiffness. For materials comprising this structure, a new type of sandwich composite, made with a 3D fabric reinforcement structure, was independently developed. A sandwich composite is a lightweight composite with practical mechanical properties, manufactured using compression moulding techniques. The 3D fabrics were produced by sewing jute yarns having configurable structures using Kevlar fibre threads, while an epoxy resin was impregnated into the 3D fabrics, achieving a more uniform resin and voids distribution and thus a better polyurethane resin impregnation for the sandwich composite. Jute composite panels were used to form the upper and lower skins during the compression moulding process. The composites had been subjected to compression, flexural and impact tests, and their fracture surfaces had been characterised by scanning electron microscopy (SEM). Mechanical tests showed that the compression and flexural strengths of the composites markedly increased, reaching 21.4 and 18.5 MPa respectively, which was approximately 7.7 and 3.8 times higher than similar properties of the blank composites without 3D fabrics. SEM micrographs of the composites showed the presence of jute fibre pull-outs in the 3D fabrics and the existence of voids in the composite.