Long period stacking structures observed in Mg97Zn1Y2 alloy

Effects of Alloying Elements on Stacking Fault Energies and Electronic Structures of Binary Mg Alloys: A First-Principles Study

“…The distance between two alloying element is larger than 11 Å to avoid the interaction between the elements. [39,51] The present setting is also in line with the experimentally determined concentrations of alloying element in the fault layers of Mg alloys, typically lower than 10 at% such as 2 ± 1 at%Zn-4 ± 2 at%Y, [52] 7 at%Zn-6 at%Y, [53] 6 at%Zn-9 at%Y, [54] and 3 at%Zn-6at%Y [53] in the alloys of Mg-1 at%Zn-2 at%Y. The different concentration of alloying elements is likely the reason for the discrepancy in reported data from Muzyk et al [23] and Zhang et al [22,24] Since the local chemical environments for alloying elements in I1 (ABC), I2 (ACB), and EF (ACB) are similar to that of FCC, the calculated stacking fault energies and the Mg-X supercell volumes are plotted in Figure 3 with respect to the volume of each individual alloying element X in the FCC structure.…”

Liquid-Solid Equilibrium and Intermediate Phase Formation during Solidification in Mg-1.3 at%Zn-1.7 at%Y Alloy

“…In addition, the resultant chemical compositions analyzed by WDS indicate nearly constant values for both the and X phases, as shown in Table 6, and this indicates that the sample at 793 K is in a thermodynamic equilibrium. Itoi et al 6) investigated the microstructure in the 97Mg-1Zn-2Y (at%) alloy using transmission electron microscopy and suggested that an 18R-type LPSO structure with the composition of 91Mg-3Zn-6Y (at%), which was considered to be the same structure as the X phase reported by Luo et al…”

“…[2][3][4] Although the strengthening mechanism of Mg-Y-Zn alloys is less well understood, it is considered to be mainly due to solution hardening of Y in the Mg solid solution ( phase) and precipitation hardening by the intermediate phase (X phase). 5) It is certain that the X phase has distinctive long-period stacking ordered (LPSO) structures, which vary with the alloy composition or heat treatment, 6) and it is considered to have a significant effect on the mechanical properties of this alloy. As a matter of course, the establishment of a phase diagram is important for efficient alloy development and optimization of manufacturing processes.…”

Effect of Extrusion Parameters on Mechanical Properties of Mg<SUB>97</SUB>Zn<SUB>1</SUB>Y<SUB>2</SUB> Alloys at Room and Elevated Temperatures

“…The Mg-Zn-RE alloys are composed of anMg matrix phase and a long-period stacking ordered (LPSO) structure phase. [5][6][7][8][9][10][11][12][13][14] The LPSO phase-containing Mg alloys that are hot-extruded exhibit high tensile yield strength (>350 MPa) and moderate elongation (>5%) at room temperature, and high tensile yield strength (>300 MPa) at 473 K. [4][5][6][7]15) It was reported previously that the mechanical properties of extruded alloys improved owing to -Mg matrix grain refinement by dynamic recrystallization (DRX), LPSO phase dispersion, and kink-deformation band formation in the LPSO phase. [16][17][18][19][20][21] Meanwhile, feasibility studies of the LPSO phase-containing Mg-Zn-RE alloys have been under way.…”