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Engineering stress -compressive strain curves of all Cr-based thin films recorded during in situ micropillar compression experiments. The data is arranged according to the predominant material response, hence results for Cr and Cr 1.03 B 2 are merged in the center section, whereas the results for Cr 0.94 N and Cr 1.79 O 3 are included in the right-hand section. Note the extended plastic deformation of Cr and Cr 1.03 B 2 after reaching the yield point, contrary Cr 0.94 N and Cr 1.79 O 3 are characterized by consecutive strain burst events and a lack of deformation stability. The mean value and standard deviation of the yield stress are included for each thin film in the left-hand section.

Engineering stress -compressive strain curves of all Cr-based thin films recorded during in situ micropillar compression experiments. The data is arranged according to the predominant material response, hence results for Cr and Cr 1.03 B 2 are merged in the center section, whereas the results for Cr 0.94 N and Cr 1.79 O 3 are included in the right-hand section. Note the extended plastic deformation of Cr and Cr 1.03 B 2 after reaching the yield point, contrary Cr 0.94 N and Cr 1.79 O 3 are characterized by consecutive strain burst events and a lack of deformation stability. The mean value and standard deviation of the yield stress are included for each thin film in the left-hand section.

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Fatigue failure through sustained loading of ductile materials manifests in irreversible motion of dislocations, followed by crack initiation and growth. This contrasts with the mechanisms associated with brittle ceramics, such as nanostructured physical vapor deposited thin films, where inhibited dislocation mobility typically leads to interface-c...

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Context 1
... stress ( σ eng ) vs. compressive strain ( ε comp ) curves from uniaxial compression tests of micropillars prepared from all Cr-based thin films are summarized in Fig. 7 . In addition, Fig. 8 contains exemplary SEM micrographs of compressed micropillars to further elucidate the observed deformation behavior. Regarding the calculated yield strengths (see Fig. 7 , left column), strong similarities were found with the fracture limits depicted in Figs. 6 . Although the materials were stressed in the ...
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... ( σ eng ) vs. compressive strain ( ε comp ) curves from uniaxial compression tests of micropillars prepared from all Cr-based thin films are summarized in Fig. 7 . In addition, Fig. 8 contains exemplary SEM micrographs of compressed micropillars to further elucidate the observed deformation behavior. Regarding the calculated yield strengths (see Fig. 7 , left column), strong similarities were found with the fracture limits depicted in Figs. 6 . Although the materials were stressed in the opposite regime, the material response showed that Cr 1.03 B 2 again obtains the highest yield strength at σ y ∼ 8.9 ±0.5 GPa, followed by Cr 0.94 N and Cr 1.79 O 3 with values of σ y ∼ 6.0 ±0.4 and ...
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... with previous values obtained for nanocrystalline bulk Cr [72] . Moreover, the compression tests reveal vastly different stress-strain responses past the yield point, from which varying "levels" of plasticity can be deduced. Most prominent, both Cr and Cr 1.03 B 2 show very similar behavior, with extensive plastic flow upon reaching σ y (see Fig. 7 center column as well as Fig. 8 a-b and 8e-f). Instead of forming distinct slip planes, the Cr pillars show uniform compression and bulging, next to crack initiation along column boundaries. The homogeneous plastic deformation can be attributed to the polycrystallinity of the material, preventing deformation in a preferred orientation. ...
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... (see Fig. 4 ), the observed deformation could be attributed to shearing along the { 10 1 1 } 11 2 0 slip plane (yet, detailed TEM analysis would be needed for clarification). Contrary, Cr 0.94 N and Cr 1.79 O 3 pillars exhibit a strongly brittle behavior, being characterized by discrete strain burst events and a lack of deformation stability (see Fig. 7 right column as well as Fig. 8 c-d and 8g-h). Especially for CrN, previous studies have also reported on significant material densification and plastic flow during nanoindentation experiments [75] , clearly contrasting to the observed material response. A possible explanation could lie in the varying deposition conditions or that ...