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In this study, two AZ91 samples were produced by compression at 200 °C and 350 °C, respectively. The microstructure of the samples and their effect on deformation were studied. The results show that the deformation mechanism is slipping, twinning and shear banding at low temperature due to the low compression temperature. The stacking fault energy of alloy can be increased by the increase of adiabatic temperature, the dislocations gather at the shear band, resulting in the increase of hardness, which is not conducive to deformation. At high temperature, there were a large number of fine second phases precipitated at the shear bands. This second phase provides nucleation site for recrystallization, and dislocation energy storage in the shear band provides energy for recrystallization, resulting in recrystallization nucleation and growth at the shear bands. Discontinuous dynamic recrystallization weakened texture intensity.

As a typical dual-phase titanium alloy, Ti-6Al-4V has a complex phase transformation process, which is sensitive to temperature parameters and difficult to control its microstructure. To further master the law of phase transformation of Ti-6Al-4V titanium alloy and make a reasonable heat treatment system, different heat treatment systems in β single-phase region and (α+β) two-phase region were made for Ti-6Al-4V titanium alloy, and the phase transformation process and microstructure growth rate of different heat treatment processes were studied by high-temperature confocal microscope. At 1050 °C and 1200 °C in the β single-phase region, the β grain size increases with the prolongation of the holding time and the increase of the holding temperature. The tissue growth rate of the α phase was higher than 1200°C in the cooling process after 1050°C incubation, which was 2.88 μm/s. Based on the heat preservation in the single-phase region, the second heat preservation was carried out for the two-phase region of Ti-6Al-4V titanium alloy at 850 °C and 900 °C. The study found that when the holding temperature was 850°C, the fastest growth rate of the α phase was 4.64 μm/s, which was greater than 3.29 μm/s when the holding temperature was 900°C.