Electromagnetic interference (EMI) shielding materials have received considerable attention in recent years. The EMI shielding effectiveness (SE) of materials depends on not only their composition but also their microstructures. Among various microstructure prototypes, porous structures provide the advantages of low density and high terahertz wave absorption. In this study, by using carbonised wood (CW) as a template, 1-mm-thick MAX@CW composites (Ti₂AlC@CW, V₂AlC@CW, and Cr₂AlC@CW) with a porous structure were fabricated through the molten salt method. The MAX@CW composites led to the formation of a conductive network and multilayer interface, which resulted in improved EMI SE. The average EMI SE values of the three MAX@CW composites were > 45 dB in the frequency of 0.6-1.6 THz. Among the composites, V₂AlC@CW exhibited the highest average EMI SE of 55 dB.

In this study, Ti₃(Al,Ga)C₂/Al₂O₃ composites were successfully synthesized by in situ hot pressing at 1350 ℃ for 2 h using Ti, Al, TiC, and Ga₂O₃ as raw materials. X-ray diffraction and scanning electron microscopy were used for characterizing the phase identities and microstructures of the sintered composites. The dependence of the Vickers hardness and flexural strength on the Al₂O₃ content was found to be in single-peak type. Ti₃(Al_0.6,Ga_0.4)C₂/10.3vol%Al₂O₃ composite exhibited significantly improved mechanical properties. Vickers hardness and flexural strength of the composite reached 6.58 GPa and 527.11 MPa, which were 40% and 74% higher than those of Ti₃AlC₂, respectively. Formation of solid solution and incorporation of second phase of Al₂O₃ resulted in the opposite influence on the fracture toughness. Finally, the hardening and strengthening mechanisms were discussed in detail.