The

The

MAPK inhibitor maximum misorientation angle ψ of the crystal lattice, which characterizes the degree of structure fragmentation, was found from azimuthal tailing of diffraction reflections compared to single-crystalline samples. The sizes of fragments were measured by electron microscopy (microscope PREM-200, Moscow, USSR). Results and discussion γ-α-γ transformations X-ray studies of alloy 1 have shown that all the austenitic reflections present in the single-crystalline samples are washed out in the azimuthal direction after reverse α-γ transformation. On the pole figure (homostereographic projection), the centers of all initial and reversed austenitic reflections coincided at the region of measurement accuracy (1° to 2°). Azimuthal tailing of reflections monotonously increased with the increase of the quantity of transformation cycles (Figure  1A,B,C,D). At the same time, the angle ψ of martensite was always less than that of Sepantronium molecular weight austenite (Figure  2A,B). Debye lines on the Ilomastat mw X-ray pattern filled up in the azimuthal direction. Hence, the rotational X-ray pattern of single-crystalline samples after 35 to 50 γ-α-γ transformations was the same as that of a textured polycrystalline sample. After 80 to 120 γ-α-γ cycles, the diffraction pattern displays practically continuous lines of austenite. It indicates

a practically full recrystallization of austenite and a transformation of the initial single crystalline into a polycrystalline sample. Different azimuthal tailing of the γ and α phase reflections qualify the different degrees of crystal lattice fragmentation of the austenite and the martensite phase, respectively. Figure 1 X-ray patterns of alloy 1 single crystal in the austenitic

state (f.c.c.), FeK α radiation. Initial state (A) and after 1 (B), 10 (C), and 80 (D) γ-α-γ transformations. Figure 2 Misorientation angle ψ of austenite (1) and martensite (2) in alloys 1 (A) and 2 (B). N, number of thermocycles. Electron microscopic investigation has shown that in the process of thermocycling, subgrain boundaries were created in reversed austenite. These boundaries were formed by dislocations generated by repeated γ-α and α-γ transformations. Tolmetin At a certain stage, subgrain boundaries form the observed fragments in the initial austenite grains. After 10 to 20 cycles, the decomposition of the reflections into three to five components was observed (Figure  1B) parallel with the progress of azimuthal tailing of reflections on the electron diffraction pattern that provide evidence for the formation of additional subgrain boundaries at this stage. In reversed austenite, the fragment size decreased with increasing number of transformation cycles. After 30 cycles, the major fraction of fragments was in the range 0.2 to 0.8 μm. After 80 to 100 cycles, the size of fragments reached the nanoscale level (about 100 nm).

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