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Abstract The free surface effect on the grain crystallography and morphology during recrystallization has been studied in stable Goss {110}〈001〉 and brass {110}〈112〉 - oriented single crystals of Al-1%wt.Mn alloy. The samples were plane strain compressed up to a strain of about 0.5 to develop a homogeneous structure comprising two sets of symmetrical microbands and then lightly annealed. The variation of recrystallization after annealing was then analysed by optical microscopy and SEM/EBSD on different cross-sections. The results are discussed in terms of the misorientation angle and axis distributions. The free surface provokes high frequency nucleation leading to a small grain size compared to internal sections of the bulk sample. However, the free surface and surface 'quality' do not modify the orientations of the recrystallized grains, i.e. similar groups of recrystallized grain orientations were observed for all sections. This leads to a strong misorientation relation between deformed/recovered area orientations and the limited number of groups of recrystallized grain orientations, basically the same as those observed during bulk recrystallization of similar crystals. Highlights • The free surface provokes high frequency nucleation. • The free surface and surface 'quality' do not modify the orientations of the recrystallized grains. • The misorientation relations across recrystallization front are similar for all sections of both orientations. [ABSTRACT FROM AUTHOR]

Alloys of titanium and oxygen have demonstrated increased tensile strength, and they show promise for a range of applications. However, the microstructure and the mechanisms of high-oxygen titanium alloy deformation remain uncertain. To address this gap in knowledge, we investigated the tensile properties and deformation mechanisms of texture-controlled Ti–O alloys with high oxygen contents. We created Ti–O alloys with oxygen contents of 0.058%, 0.21%, 0.41%, 0.65%, and 0.71% by mass. These alloys possessed 0001 10 1 ¯ 0 texture, and they were deformed along the rolling direction. We found that oxygen content was correlated with increases in 0.2% proof stresses and tensile strengths, which conformed to the solid-solution strengthening law. All specimens exhibited total elongation of higher than 20%. Twin deformation had minimal effect on strength and elongation, and the major deformation mode was for slip deformation. The uniform elongation and gradient of the work hardening rate increased at oxygen contents above 0.61 mass%. As oxygen content increased, double slipping occurred in more grains. That is because pyramidal slip is activated, and its operation induces the crystal orientation to the stable orientation under tensile deformation. Double slipping easily occurs in a grain with stable orientation. Therefore, dislocations were frequently cut and tangled with each other. As a result, the gradient of the work hardening rate increased, and uniform and total elongation increased in Ti–O alloys with abundant oxygen. These findings are useful to extend oxygen utilization as an alloying element in Ti. • The deformation microstructures of high-oxygen Ti–O alloys were investigated. • Texture controlling is useful to increase uniform elongation and inhibit twinning. • The range of oxygen content utilized as alloying element in Ti can be extended. • Pyramidal slip is active as a secondary slip system in high-oxygen Ti–O alloys. • The relationship between strengthening amount and O content was analyzed. [ABSTRACT FROM AUTHOR]