Fabrication, oxidation and creep behavior of Ti2AlN composites

Abstract

In order to enhance the limited information on elevated temperature stability of MAX phase materials, Ti2AlN MAX phase composites were fabricated in a two-step procedure and subsequently tested regarding their oxidation and creep behavior. Furthermore, commentary testing on material enhanced with different amount of Al2O3 fibers was performed. The compressive creep was investigated in the temperature range of 900–1200 °C under stresses ranging from 20 to 100 MPa, with a loading direction parallel and perpendicular to the compression direction during sintering. The oxidation behavior was characterized, demonstrating excellent oxidation resistance of the samples up to 1200 °C. Supported by microstructural investigations, the impact of the texturing of the matrix grains, the content and the orientation of Al2O3 fibers, as well as that of the interfaces between matrix grains and the Al2O3 fibers were investigated. De-cohesion and cracks formed at the triple junctions of the MAX phase grains indicate grain boundary sliding as predominant creep mechanism for the composites.