Fig. 3: Mechanical properties of the TiNbZr-O-C-N MISS alloys and the reference equiatomic TiNbZr base alloy.

a Compressive engineering stress-strain curves of the base, O-6, O-6A, and O-12 alloys measured at ambient temperature. The curves are shown only up to 50% strain to clearly reveal the yield points (the compressive deformation of the O-6 and O-12 alloys is even higher, above a total strain of 65%). The inset in a shows the O-12 MISS alloy pillar prior to compression. The arrow in a indicates the onset of strain bursts in the amorphous O-6A alloy, due to shear banding, leading to early failure. b Load-displacement curves measured by bending of cantilever beams, fabricated from the base, O-6A, and O-12 alloys. The inset in b shows the position of the diamond indenter tool, deforming the O-12 cantilever. SEM images presenting c micro-pillars and d cantilevers of the O-12 and O-6A alloys after deformation. Some shear bands in the deformed O-6A amorphous alloy are indicated by the arrows in c and d, respectively. e TEM images revealing the grain structure evolution of the O-6 MISS alloy with increasing compressive strain. After ~15% strain, the originally columnar grains have become curved. As the strain increases to an intermediate deformation state of ~45%, both, curved columnar grains and newly formed sub-grains are found. With further increasing the strain to ~65%, the initially columnar nanograins have become globular.