PSI - Issue 40

S.V. Danilov et al. / Procedia Structural Integrity 40 (2022) 112–117

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S.V. Danilov at al. / Structural Integrity Procedia 00 (2022) 000 – 000

Fig. 1. Microstructure (in the form of EBSD orientation maps) of the central areas of the 06Mn2MoNb steel plates after thermo-mechanical controlled processing according to different modes: (a) – I; (b) – II; (c) – III.

Fig. 2. Texture of the central layers of the pipe steel plates in the form of cross-sections of orientation distribution functions obtained by means of EBSD at φ 2 = 0°, φ 2 = 45°: (a) – (c) – orientation distribution function in the form of distribution intensity of pole density after different modes ((a) – I, (b) – II, (c) – III); (d) – orientation distribution function standard grids with plotted ideal orientations in the form of crystal unit cells (view from TD). Separations appeared in the fracture areas of all the specimens (Fig. 3, а – с), even though the fractures occurred at room temperature. Similar separations often appear in the fracture areas of the specimens after Charpy impact testing (Pyshmintsev and Smirnov (2019) and Pyshmintsev et al. (2016)). The plane on which the separations lied (especially in the central area of the reduced sections) was almost parallel to the TMCP rolling plane. Singular separations were common for specimens after modes I and II, while specimens after mode III demonstrated tendency towards numerous separations. It is also important to note that even though the nature of all the fractures was ductile, the surfaces of the metal at separation sites corresponded to brittle fracture (Fig. 3, с).