Reversion of a Parent {130}<310>α" Martensitic Twinning System at the Origin of {332}<113>β Twins Observed in Metastable beta Titanium Alloys

P. Castany (1) , Y. Yang (1) , E. Bertrand (2) , T. Gloriant (1)

1 ISCR - Institut des Sciences Chimiques de Rennes
2 IMN - Institut des Matériaux Jean Rouxel

In bcc metastable β titanium alloys, and particularly in superelastic alloys, a unique {332}⟨113⟩ twinning system occurs during plastic deformation. However, in situ synchrotron x-ray diffraction during a tensile test shows that the β phase totally transforms into α" martensite under stress in a Ti-27Nb (at. %) alloy. {332}<113>β twins are thus not formed directly in the β phase but are the result of the reversion of {130}<310>α'' parent twins occurring in martensite under stress. The formation of an interfacial twin boundary ω phase is also observed to accommodate strains induced during the phase reversion.

Mots clés: x-ray-diffraction; gum metal; ti-alloys; deformation; omega-phase-transformation; superelasticity; ti-24nb-0.5n; stability; youngs modulus; mechanical-properties

Domaines: Matériaux

P. Castany, Y. Yang, E. Bertrand, T. Gloriant. Reversion of a Parent {130}<310>α" Martensitic Twinning System at the Origin of {332}<113>β Twins Observed in Metastable beta Titanium Alloys. Physical Review Letters, 2016, 117 (24), pp.245501. ⟨10.1103/PhysRevLett.117.245501⟩. ⟨hal-01438121⟩