Manufacturing, Properties, and Applications of Porous Ti₂AlC: A Review

Porous Ti₂AlC, a member of the MAX phase family of nanolaminated ternary carbides and nitrides, has attracted increasing attention due to its unique combination of metallic and ceramic properties. This review summarizes recent advances in the fabrication, structure-property relationships, and applications of porous Ti₂AlC. Various processing routes, including incomplete sintering, sacrificial templating, replica techniques, gel casting, extrusion, and direct ink writing, are compared in terms of achievable porosity, pore morphology, and structural control. Particular emphasis is placed on the role of porosity in tailoring mechanical performance, thermal conductivity, and high-temperature oxidation resistance, based on available literature data. Recent progress in applications of porous Ti₂AlC and related MAX phases is also discussed, including their use in filtration, membrane supports, heat exchangers, electrochemical systems for hydrogen evolution, and as preforms for lightweight interpenetrating metal/MAX phase composites. Finally, current challenges and future research directions are identified, highlighting the need for improved control of porosity and a deeper understanding of structure-property relationships.