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Mg 2 Si composite was added to Al-Si ller metal for aluminium alloy vacuum brazing via in situ synthesis. Spreading area method was used to measure the wettability of the brazing alloy on the parent metal in vacuum. The ller metal wetting area increased with increasing Mg 2 Si content. The compound within the interface was examined with an electron probe and the following results were obtained: Mg 2 Si content of the brazing interface was lower than that of ller metal, Mg 2 Si was distributed into both sides of the interface and arranged in block, grain and short rod-like shapes. Si crystal had a primarily needle-like structural arrangement. The elemental distribution on both sides of the interface was analysed using thread scanning method. A solid solution of Mg was formed in the interior parts of the grain in the parent metal. The solid solution content decreased as the distance from the interface increased.

Boron carbide (B4C) ceramics were synthesized by spark plasma sintering at a temperature between 1600 and 2050 °C without employing any sintering additives. The effect of sintering process parameters, such as temperature, holding time, pressure, hearting rate, and pulsed electric current, and the particle size of the raw powder on the densification behavior and mechanical properties of B4C ceramics, were comprehensively and systematically investigated. Hardness and fracture toughness of B4C that has a density close to the theoretical value were found to be 33.5 ± 0.2 GPa and 3.21 ± 0.13 MPa·m1/2, respectively. Electron backscatter diffraction (EBSD) analysis revealed no abnormal growth of grains due to an increase in holding time and pressure. Twin structures present in ceramics are beneficial for their mechanical performance.