A detailed study of texture changes during alpha–beta processing of a zirconium alloy

Co-deformation and dynamic annealing effects on the texture development during alpha–beta processing of a model Zr-Nb alloy

“…At lower temperatures and high α volume fractions (< 20% β), the texture is typically weaker and is similar to the rolling texture of single α alloys, with strong alignment of the basal 0002 poles along ND [6,11]. At higher temperatures and high β volume fractions (> 70% β) the room temperature α-texture is also weaker, mainly due to the randomising effect of phase transformation [6,8]. As it is challenging to measure, the β texture has not been studied as extensively as the α texture, but our recent work on Zr-2.5Nb [6] suggests that the strengthening of the α texture is accompanied by a strengthening of the β texture, when the volume fraction of α:β is about 50:50.…”

“…Zr-2.5Nb and Ti-6Al-4V (Ti-64) alloys are usually hot worked via α + β forging, extrusion [3][4][5] or rolling [2,[6][7][8][9][10]. The characteristic α-texture that develops is a strong transverse (TD) alignment of the 0002 basal poles [2,[6][7][8][9][10], and alignment of the prismatic 101 $ 0 poles along RD (ED for extrusion), and therefore the main texture component is near {112 $ 0}⟨101 $ 0⟩ (often also referred to as 0002||TD). In some cases, the 0002 pole deviates from TD, and the dominant component becomes {112 $ 1}⟨101 $ 0⟩ [6,9].…”

“…During hot-rolling, the texture strength depends on the processing temperature and is strongest when both phases are present in similar volume fractions [6,8]. At lower temperatures and high α volume fractions (< 20% β), the texture is typically weaker and is similar to the rolling texture of single α alloys, with strong alignment of the basal 0002 poles along ND [6,11]. At higher temperatures and high β volume fractions (> 70% β) the room temperature α-texture is also weaker, mainly due to the randomising effect of phase transformation [6,8].…”

“…At higher temperatures and high β volume fractions (> 70% β) the room temperature α-texture is also weaker, mainly due to the randomising effect of phase transformation [6,8]. As it is challenging to measure, the β texture has not been studied as extensively as the α texture, but our recent work on Zr-2.5Nb [6] suggests that the strengthening of the α texture is accompanied by a strengthening of the β texture, when the volume fraction of α:β is about 50:50. With increasing β volume fraction, the α transverse texture component strengthens first, during which the β γ-fibre (111 in ND) disappears to be replaced by a very strong rotated cube component and a weaker {111}〈112〉 component [6].…”

“…Like the α texture, the β texture weakens at higher temperatures, and changes to the more common bcc α and γ fibre textures [6,10].…”