Ternary compounds denominated by the structure formula Mn+1AXn (MAX) phases comprise an extended family of layered, hexagonal transition metal carbides and nitrides. Due to their unique crystal chemistries and layered atomic structures, MAX phase materials combine many unique attributes of both ceramics and metals. These include low density, easy machinability, high thermal and electrical conductivities, thermal shock and damage tolerance, and excellent high-temperature resistance to oxidation and corrosion. These remarkable properties attract growing interest on the fabrication, characterization and implementation of MAX phase materials considered for structural and nonstructural applications under extreme conditions in the form of both bulk materials and thin films.
Alumina-forming MAX phases, like Ti2AlC and Cr2AlC with self-healing capabilities, have shown great potential in applications as high-temperature oxidation and corrosion resistant coatings. However, deposition of phase-pure polycrystalline MAX phase coatings, either by spraying technology or physical vapor deposition (PVD), often remains a challenge. The retention of stable competing phases, like binary carbides and intermetallics, degrade the performance of the coatings. ... mehr