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Temperature Effect on Stacking Fault Energy and Deformation Mechanisms in Titanium and Titanium-aluminium Alloy.

ABSTRACT: Alloying elements have great influence on mechanical properties of metals. Combining dislocation characterization and in-situ transmission electron microscope straining at ambient and liquid-nitrogen temperature in high-purity titanium and Ti-5at%Al, we investigated the modulation of Al on dislocation behaviours as temperature changed. It reveals that segregation of Al at edge dislocation cores in Ti-5at%Al generates strong obstacles, promoting room temperature cross-slips. However, the effect of Al on reducing stacking-fault energy (SFE) as decreasing temperature is significant. Consequently, the lower SFE in Ti-5at%Al results in ordinary planar dislocation slip while massive dislocation cross-slips occurred in Ti at liquid-nitrogen temperature.

SUBMITTER: Zhao B

PROVIDER: S-EPMC7033204 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature

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Temperature Effect on Stacking Fault Energy and Deformation Mechanisms in Titanium and Titanium-aluminium Alloy.

Zhao Beikai B Huang Peng P Zhang Libo L Li Suzhi S Zhang Ze Z Yu Qian Q

Scientific reports 20200220 1

Alloying elements have great influence on mechanical properties of metals. Combining dislocation characterization and in-situ transmission electron microscope straining at ambient and liquid-nitrogen temperature in high-purity titanium and Ti-5at%Al, we investigated the modulation of Al on dislocation behaviours as temperature changed. It reveals that segregation of Al at edge dislocation cores in Ti-5at%Al generates strong obstacles, promoting room temperature cross-slips. However, the effect o ...[more]

PMID: 32080279

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