Graphene reinforced aluminum matrix composites (GRAMCs) with improved thermal conductivity were prepared via a pH-controlled self-assembly process that involved adjusting the concentration of dispersed graphene oxide (GO) solutions. Uniform dispersion was achieved using GO coating on the aluminum (Al) surfaces. Graphene encapsulated Al powders (Al/GO) were sintered through spark plasma sintering (SPS) to prepare bulk composites, these were then analyzed to determine the thermal and mechanical properties. The density of the Al/GO composites was determined to be 99% or more compared to the theoretical density of pure Al. The Vicker’s hardness and thermal conductivity increased by about 47% and 15% more than the pristine Al bulks. These processes can improve properties of the thermal interface between GO and Al, enabling uniform coating without a crosslinking agent. An Al/GO composite, fabricated through the pH-controlled self-assembly process, should be useful for various applications requiring to high thermal conductivity.

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Although many bone graft materials have been developed, powder graft materials are somewhat difficult to use in surgery. To solve this problem, a bone graft material in the form of a viscous paste was prepared. Hydroxyapatite was used as a bone graft material, and methyl cellulose was used to impart viscosity. Three cases of samples were prepared, and freeze-dried block type and sintered specimens were made from the paste. The recrystallization of the graft material in a simulated body fluid and the degree of graft adhesion with a tooth were observed by scanning electron microscopy (SEM). The test for cytotoxicity was carried out and the sample was grafted into the back of a mouse to confirm the presence or absence of side effects in the animal's body. Based on these investigations, composites of this type are expected to be applicable for bone grafts.

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