Dynamic aging in an Fe–Ni–Al alloy upon megaplastic deformation. Effect of the temperature and deformation rate

Atomic Order and Submicrostructure in Iron Alloys at Megaplastic Deformation

“…The activity of deformation-assisted dissolution of the intermetallic γ′ phase depends on the peculiarities of intermetallics and is realized at large critical deformations of ε ≥ 4 [5]. Besides, on lowering the temperature of deformation from room to cryogenic in value, in the works [13][14][15][16] the acceleration of the dissolution of intermetallics was established. The quantitative estimates of the dissolution and precipitation of intermetallics were carried out based on the content of nickel in the FCC matrix of Fe-Ni-(Ti, Al, Si, Zr) alloys are not of a low-melting series; however, in these alloys an active atomic redistribution at the rolling to high reduction degrees has been revealed as a consequence of the deformation-induced dissolution of intermetallics in a metallic matrix.…”

“…The appearance of the works refs. [5,[9][10][11][12][13][14][15][16][17][18][19][20][21][22][23] on the induced dissolution of disperse particles, formation of supersaturated solid solutions, and dynamical aging, namely, accelerated ordering and decomposition with the formation of secondary phases that strengthen a metallic matrix, has enabled a development in studies on deformation-induced nanostructuring and mechanosynthesis. So, the effect of the conditions of mechanical activation on the mechanism of transformations and on the final modified structure of steels and alloys has been elucidated.…”

“…The authors of these works were initiators of the first studies on anomalous low-temperature phase transformations [24][25][26][27][28][29][30][31]. Analysis of the effect of the temperature and rate of large plastic deformation on the mechanism of phase transformations, as well as a comparison with the case of irradiation action, has become a specific feature of these works [13][14][15][16][17][18][19][20]. An attempt to compare the cases of deformation action and irradiation by high-energy elementary particles is explained by the generation in both cases of mobile point defects, namely, vacancies and interstitial atoms.…”

“…An attempt to compare the cases of deformation action and irradiation by high-energy elementary particles is explained by the generation in both cases of mobile point defects, namely, vacancies and interstitial atoms. The participation of point defects was analyzed at the initial stages of the (i) phase transformations in the form of the processes of the formation and destruction of short-range clustering in binary Fe-(Mn, Cr, Ni) iron alloys [18][19][20], of (ii) the formation and decomposition of the solid solutions of ferritic and austenitic Fe-(Mn, Cr, Ni)-N and Fe-Ni-C steels, supersaturated by nitrogen and carbon [10][11][12]19,[21][22][23], as well as of (iii) the dissolution and precipitation of intermetallic particles in ageing Fe-Ni-(Ti, Al, Si, Zr) alloys [13][14][15][16][17].…”

“…To execute large plastic deformation and to control the conditions of the experiment, along with practically important external actions, such as milling in a ball mill (BM) [9][10][11], frictioning at friction treatment [21,32,33], and reducing at rolling [15], the high pressure torsion (HPT) method (of pressure torsion) in Bridgman anvils [12][13][14][15][16][17][18][19][20][21]23] was used. The method of HPT permits (i) the creation of high degrees of true deformation (ε~ 9) without the failure of samples and (ii) the control of the degree, rate, and temperature of deformation.…”