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Deformation Induced Hierarchical Twinning Coupled with Omega Transformation in a Metastable ?-Ti Alloy.

ABSTRACT: Hierarchical twinning, at multiple length scales, was noted in a metastable body-centered cubic (bcc) ?-titanium alloy on tensile deformation. Site-specific characterization within the deformation bands, carried out using EBSD and TEM, revealed {332} <113> type primary bcc twins, containing different variants of secondary and tertiary twins, as well as the formation of stress-induced martensite (?"). Within the primary {332} <113> type twin, "destruction" of the prior quenched-in athermal ? phase was observed, while a stress-induced ? phase reforms within the tertiary twins, revealing the intricate nature of coupling between deformation twinning and displacive ? transformation.

SUBMITTER: Mantri SA

PROVIDER: S-EPMC6362253 | biostudies-literature | 2019 Feb

REPOSITORIES: biostudies-literature

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Deformation Induced Hierarchical Twinning Coupled with Omega Transformation in a Metastable β-Ti Alloy.

Mantri S A SA Sun F F Choudhuri D D Alam T T Gwalani B B Prima F F Banerjee R R

Scientific reports 20190204 1

Hierarchical twinning, at multiple length scales, was noted in a metastable body-centered cubic (bcc) β-titanium alloy on tensile deformation. Site-specific characterization within the deformation bands, carried out using EBSD and TEM, revealed {332} <113> type primary bcc twins, containing different variants of secondary and tertiary twins, as well as the formation of stress-induced martensite (α"). Within the primary {332} <113> type twin, "destruction" of the prior quenched-in athermal ω phas ...[more]

PMID: 30718639

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