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The present study focused on investigating the growth mechanism of -oriented grains from low strain to high strain. The orientation characterizations of Ti-5Al-5Mo-5V-1Cr-1Fe alloy under different strain rates and compression temperatures were studied by EBSD technique. The dynamic recrystallization grains were selected by the GOS method to reveal the effect of dynamic recovery and recrystallization on texture evolution. 2. Materials and Experimental Procedures The Ti-5Al-5Mo-5V-1Cr-1Fe alloy used in this study was obtained from a hot forged bar with a diameter of 350 mm. The composition of the alloy was 5.23 Al, 4.85 Mo, 4.93 V, 0.92 Cr, 1.17 Fe, and balance Ti. The β-α+β transus temperature of Ti-5Al-5Mo-5V-1Cr-1Fe was approximately 1143 …show more content…

1b. The initial grains of the alloy are equiaxed with a size of approximately 80–100 μm. Figure 1. {100} Pole figure (a) of the as-received Ti-5Al-5Mo-5V-1Cr-1Fe alloy bar and original microstructure (b) after solution treatment. 3.2. Texture Evolution during Hot Compression Deformation parameters including the strain and strain rate exert an important influence on the texture components during hot compression around β transus temperature. Figure 2 shows the EBSD test results of the samples compressed at different strain rates of 1/s, 0.1/s, and 0.01/s by reductions of 20%, 40%, 60%, and 80% at 1153K. Figure 3 shows the fractions of two main fiber textures including and fiber textures. The two main texture components of the sample with 1/s strain rate nearly retained the same volume fraction after 40% compression. The intensity of fiber texture increased with decreasing strain rate. Especially, the sample compressed with 80% reduction under 0.01/s strain rate only showed texture. It can be deduced that at the initial stage of compression, the strain rate has a weak effect on the texture evolution. With increasing deformation, low strain rate may be benefit for the development of texture and texture is gradually weakened or even vanished. Figure 2. Orientation maps by EBSD under different parameters, a1–a4 are under 1/s with 20%, 40%, 60%, and 80% reduction, b1–b4 are under 0.1/s with 20%,

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