On the fracture behavior of Cr2AlC coatings

Bulk MAX phase materials were investigated heavily in the last decades due to their advantageous combination of metallic and ceramic properties. In recent years, phases also gained interest protective coatings community. Cr2AlC is a very promising material, since crystalline can be deposited at comparatively low (550 °C) substrate temperatures. Another advantage its self-healing ability. The goal this investigation was characterize fracture toughness using situ SEM micro-cantilever tests determine influence different microstructures on behavior. Surprisingly, only moderately affected by microstructure samples here, which reveal ranging from 1.8 ± 0.1 MPam1/2 2.4 0.2 MPam1/2. contrast that, it could shown that there significant increase for amorphous coating with identical chemical composition (4.1 0.5 MPam1/2) almost twice compared coatings. detrimental grain boundaries lack sample might explain formidable toughness.