Twinned silicon carbide (SiC) nanowires (NWs) reinforced Si3N4–SiOC composites were successfully fabricated through a joint process of three-dimensional printing (3DP), direct nitridation, and polymer infiltration and pyrolysis (PIP). 3DP and PIP were both addictive manufacturing processes, enabling the near net shape fabrication and microstructure designing of Si3N4–SiOC. With the increase of the PIP cycle number, the pores of Si3N4 were mostly filled with polymer-derived ceramics-silicon oxycarbide (containing SiC NWs and free carbons), which led to the increase of electrical conductivity of Si3N4–SiOC composites. With the increase of SiOC ceramics, the electromagnetic interference shielding effectiveness of Si3N4–SiOC composites increased from 2 dB to 35 dB, in which the absorption shielding effectiveness increased to 27 dB. The flexural strength of Si3N4–SiOC composites reached 63 MPa when the content of SiOC ceramics was 50.1 wt%. It is indicated that Si3N4–SiOC ceramics are a promising electromagnetic shielding and structural material.

Nano-structured yttria stabilized zirconia (YSZ)/Al2O3 nano-composite coatings were prepared by electrophoretic deposition (EPD) in acetyl-acetone/ethanol solvents under the constant voltage of 40 V. High sintering temperature may damage the metal parts and also lead to high production costs. To overcome the disadvantages of high sintering temperatures, reaction bonding of Al was taken as the approach. It was found that a powder mixture of Al and YSZ can lower the sintering temperature. YSZ/Al green composites were deposited on the MCrAlY layer applied on Inconel alloy cathode. Iodine was added to the solutions as the stabilizing agent. According to differential thermal analysis (DTA) results, embedded Al particles oxidation started at 660 °C. Sintering process for YSZ/Al2O3 nano-composite coating occurred at 1150 °C for 4 h. A lower pinholes coating with the highest density due to the constraint of the substrate was obtained.

A novel approach based on the preceramic paper method was used for the fabrication of Ti3SiC2-based material. Elemental powders of Ti, TiC, Si, C, and organic additives were used as starting materials. The Rapid Köthen process was used to fabricate the preceramic papers. The high-loaded green body of preceramic papers was heat-treated up to varying temperatures of 1300, 1400, 1500, and 1600 °C for 1 h in an Ar atmosphere. By using an excess amount of Si powder in the basic composition, the amount of Ti3SiC2 in the sintered specimen could be increased while the amount of TiC could be reduced. X-ray analysis showed that the paper-derived sample with the basic powder composition 3Ti/3TiC/3Si/C was a single phase within the resolution limit of the instrument used. The high purity of Ti3SiC2 can be explained by the partial formation of amorphous C which could not be detected by X-ray diffraction. Scanning electron microscopy analysis of fracture surfaces showed the characteristic lamellar structure of the paper-derived MAX phase.

Recent advances in alumina ceramics are focused toward innovative processing routes to improve their mechanical reliability while retaining their superior wear resistance, which might be possible if a thin layer of dense alumina can be formed on a metallic substrate such as Ti–6Al–4V with high mechanical strength. For this purpose, we propose a new two-step process in which a dense layer of Al deposited on the Ti alloy by cold metal transfer method, formed a dense Al3Ti gradient reaction layer at their interface to improve adhesion in a single step. Subsequent micro-arc oxidation treatment transformed Al layer to a graded alumina layer in which γ-alumina decreased and α-alumina increased with increasing depth. Abrasion of outer regions revealed underlying pure α-alumina regions with high Vickers hardness matching with that of sintered alumina. The designed alumina/Ti alloy hybrid can be a potential candidate for wear resistance applications.

Boron carbide (B4C) powder was consolidated at 45 MPa by Spark Plasma Sintering (SPS) for 20 min from 1450 to 2000 °C. The density of the B4C reached 99.6% at 2000 °C. A continuum model was applied to describe the densification mechanism of B4C powder under SPS conditions. The shrinkage rate was sensitive to particle size and temperature. The effect of porosity on thermal diffusion was significant, especially for small particle sizes. It appears that there is Joule heating, discharge, and electromagnetic field involved during the SPS of B4C. The current can enhance the sintering process, and it can obviously reduce the creep activation energy.