Annealing behaviour of Mg–3Al–1Zn alloy sheet obtained by a combination of high-temperature rolling and subsequent warm rolling

Improvement of stretch formability of Mg–3Al–1Zn alloy sheet by high temperature rolling at finishing pass

“…No change in the basal texture intensity occurs but the double peak is replaced by the single peak for the sheets rolled at the lowest temperature of 723 K. By contrast, the sheets rolled at temperatures higher than 798 K exhibit significantly weakened textures and the double peaks also greatly increase their splitting angles to ∼20 • in the RD. In the previous work, some of the authors reported that a significant weakening of texture may be achieved by annealing a rolled AZ31 alloy with a deformation microstructure without an occurrence of DRX [16,17], which has also been revealed to be due to discontinuous SRX at pre-existing grain boundaries [23]. However, all sheets obtained in the present study have a similar appearance of deformation microstructure (see Fig.…”

“…The large orientation gradients and the high local dislocation densities near grain boundaries are likely to induce SRX at pre-existing grain boundaries as observed in Ref. [23]. When a high density of non-basal dislocations exists, it is suggested that absorption of non-basal dislocations in boundaries may promote rotation of nuclei and/or quite small SRXed grains in various directions, which results in largely altered orientations and in turn a remarkably weakened texture.…”

“…When a high density of non-basal dislocations exists, it is suggested that absorption of non-basal dislocations in boundaries may promote rotation of nuclei and/or quite small SRXed grains in various directions, which results in largely altered orientations and in turn a remarkably weakened texture. The final annealing texture is generally also affected by subsequent grain growth [23]. It is therefore an important future work for us to investigate the type and fraction of twins as well as the SRX and grain growth behaviors during annealing for understanding the relationship between the texture formation mechanism and the rolling temperature.…”

Elastic and Damping Properties of AZ31 Magnesium Alloy Sheet Processed by High-Temperature Rolling

“…The significant reduction of basal texture intensity and the wide spread of the basal pole toward the RD and TD in the specimen rolled at 798 K are likely ascribed to the occurrence of discontinuous static recrystallization during annealing. 6,12) Tensile properties including ultimate tensile strength (UTS), 0.2% proof stress (YS), fracture elongation (FE), uniform elongation (UE), r-value and strain hardening exponent value (n-value) of the rolled specimens are summarized in Table 1. The YS and r-value increased with increasing the angle between the RD and the tensile direction, while the n-value showed a converse behavior.…”

“…[1][2][3][4][5][6][7][8][9][10][11][12] One method for enhancement of room temperature formability of magnesium alloy sheets is the use of improved rolling technologies such as shear rolling [1][2][3][4][5][6][7] and hightemperature rolling. 3,4,6,[9][10][11][12] High-temperature rolling is suggested to be one of the attractive rolling technologies, because a conventional rolling machine is directly available, if rolling temperature can be set to more than 723 K. The magnesium alloy sheet processed by the high-temperature rolling exhibits a significant weak basal texture, resulting in the excellent room temperature formability comparable to those of aluminum alloy sheets.…”