Submicron Ti ₂ AlC MAX phase powder was synthesized by molten salt shielded synthesis (MS ³ ) using a Ti:Al:C molar ratio of 2:1:0.9 at a process temperature of 1000°C for 5 hours. The synthesized powder presented a mean particle size of ~0.9 µm and a purity of 91 wt. % Ti ₂ AlC, containing 6 wt. % Ti ₃ AlC ₂ . The Ti ₂ AlC powder was sintered by pressureless sintering, achieving a maximal relative density of 90%, hence field‐assisted sintering technology/spark plasma sintering was used to enhance densification. The fine‐grained microstructure was preserved, and phase purity of Ti ₂ AlC was unaltered in the latter case, with a relative density of 98.5%. Oxidation was performed at 1200°C for 50 hours in static air of dense monolithic Ti ₂ AlC with different surface finish, (polished, ground and sandblasted) which resulted in the formation of an approx. 8 µm thin aluminum oxide (Al ₂ O ₃ ) layer decorated with titanium dioxide (rutile, TiO ₂ ) colonies. Surface quality had no influence on Al ₂ O ₃ scale thickness, but the amount and size of TiO ₂ crystals increased with surface roughness. A phenomenon of rumpling of the thermally grown oxide (TGO) was observed and a model to estimate the extent of deformation is proposed.

Electrodeposition is a simple and effective method for the synthesis of disordered hydrated vanadium pentoxide (V₂O₅·nH₂O). For the synthesis of energy storage electrodes with high power performance, electrodeposition of hydrated V₂O₅ inside carbon micropores is particularly attractive to synergize electric-double layer formation and lithium ion intercalation. Here, we demonstrate that hydrated V₂O₅ can be effectively electrodeposited in carbon micropores of activated carbon cloth. Our study indicates that carbon pores larger than 1 nm are essential for the effective decoration with hydrated V₂O₅. A thermal treatment after the electrodeposition is often used to enhance the crystal structure of hydrated V₂O₅. However, thermal annealing of the hydrated vanadium pentoxide decorated activated carbon cloth under an oxygen-rich environment at high temperature (>330 °C) leads to a significant loss of pore volume, leading to a decreased electrochemical performance. At low annealing temperature (200 °C), the vanadium pentoxide electrodeposited activated carbon cloth electrode exhibits a maximum specific capacity of 137 mA h g⁻¹ with stable cycle performance over 1600 cycles at a rate of 4C.

Near-net shape components composed of monolithic Ti₂AlC and composites thereof, containing up to 20 vol.% Al₂O₃ fibers, were fabricated by powder injection molding. Fibers were homogeneously dispersed and preferentially oriented, due to flow constriction and shear-induced velocity gradients. After a two-stage debinding procedure, the injection-molded parts were sintered by pressureless sintering at 1250 °C and 1400 °C under argon, leading to relative densities of up to 70% and 92%, respectively. In order to achieve near-complete densification, field assisted sintering technology/spark plasma sintering in a graphite powder bed was used, yielding final relative densities of up to 98.6% and 97.2% for monolithic and composite parts, respectively. While the monolithic parts shrank isotropically, composite assemblies underwent anisotropic densification due to constrained sintering, on account of the ceramic fibers and their specific orientation. No significant increase, either in hardness or in toughness, upon the incorporation of Al₂O₃ fibers was observed. The 20 vol.% Al₂O₃ fiber-reinforced specimen accommodated deformation by producing neat and well-defined pyramidal indents at every load up to a 30 kgf (~294 N).