Fig. 5: Deformation mechanisms of the CoCrNi-O MPEAs.

a Typical DF-STEM image of the O-13 MPEA upon 50% compressive strain. The inset image is the corresponding FFT pattern. Scale bar of inset is 5 1/nm. b, c Magnified images of the white dashed square regions in (a), showing a SF with a Shockley partial dislocation and a coherent twin boundary with a Shockley partial dislocation, respectively, as verified by their corresponding FFT patterns (insets). Scale bars of insets are 10 1/nm. d STEM-EELS line-scanning analysis. The insets show the BF-STEM image and EELS mapping of oxygen corresponding to the acquisition area. The white dashed lines denote grain agglomerates and the yellow arrow represents the line-scanning direction. e–h APT characterization of the structure evolution before and after compression. e Changes in spatial distribution of 16 at.% O-isoconcentration surfaces (16%-O). f 16%-O volume distribution reveals that the size of O-rich cluster becomes larger. g Nearest neighbor distance distribution for 16%-O. h Variation of calculated O-O RDFs. Source data are provided as a Source Data file.