Abstract
X-ray diffraction transmission electron microscopy, and measurements of microhardness and resistivity were used to study the formation of the orthorhombic O phase upon the α2 → O phase transformation. It has been found that the orthorhombic O phase is formed by the diffusion mechanism in the form of thin lamellar precipitates (domains). Upon subsequent growth, these domains form packets of twins with a twinning plane {110}. It is shown that the (130) twinning plane is not realized directly, but it appears as a result of joining of twin packets. No formation of an intermediate metastable phase was observed upon this transformation.
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Original Russian Text © N.V. Kazantseva, S.L. Demakov, A.A. Popov, 2007, published in Fizika Metallov i Metallovedenie, 2007, Vol. 103, No. 4, pp. 406–412.
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Kazantseva, N.V., Demakov, S.L. & Popov, A.A. Microstructure and plastic deformation of orthorhombic titanium aluminides Ti2AlNb. IV. Formation of the transformation twins upon the α2 → O phase transformation. Phys. Metals Metallogr. 103, 388–394 (2007). https://doi.org/10.1134/S0031918X07040114
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DOI: https://doi.org/10.1134/S0031918X07040114