Precipitates formed in a Mg–7Y–4Gd–0.5Zn–0.4Zr alloy during isothermal ageing at 250°C

Enhanced mechanical properties of Mg–Gd–Y–Zr casting via friction stir processing

“…An exponential drop of the high equilibrium solid solubility of Gd with decreasing temperature produces an ideal precipitation strengthening [6,7], in addition to the solid solution strengthening [8]. In the past few years, the precipitation behavior, micro alloying, and heat treatment have been widely studied, laying a foundation for optimizing the mechanical properties of the Mg-Gd-Y alloys [1,3,[9][10][11][12].…”

Twinning and dynamic precipitation upon hot compression of a Mg−Gd−Y−Nd−Zr alloy

“…Mg-RE (rare earth element) alloys is one of the vigorous alloy systems among Mg alloys [10][11][12][13][14]. Their high strength mainly benefits from their remarkable precipitation hardening and solid solution hardening.…”

Double-peak ageing behavior of Mg–2Dy–0.5Zn alloy

“…The investigations on the ageing behavior of Mg-RE-Zn alloys [15][16][17] have shown that the precipitation of coherent and noncoherent Mg-RE particle phases and the formation of LPSO phases in the supersaturated ␣-Mg solid solution play a dominant role in enhancing ageing hardening response during isothermal ageing. Honma et al's study on the ageing behavior of Mg-2.0Gd-1.2Y-1Zn-0.2Zr (at.%) alloy at 225 • C [15] revealed that the concurrent precipitations of the ␤ (bco) and ␤ 1 (fcc) particle phases lead to a significant ageing peak at 32 h and the 14H LPSO phase forms in the over-raged condition (288 h).…”

“…Yamasaki et al's investigation of the ageing behavior of Mg 97 Gd 2 Zn 1 (at.%) alloy at temperature range from 200 • C to 500 • C [16] showed that a significant ageing peak occurs at 200 • C due to the precipitation of the ␤ (orthor, Mg 7 Gd) particle phases, while 14H LPSO phases form at 350-500 • C and result only in a limited ageing hardening response. Liu et al [17] reported that during the ageing of an extruded Mg-7Y-4Gd-0.5Zn-0.4Zr alloy at 250 • C, both ␤ (cbco) and 14H LPSO phases coexist together and contribute to the peak ageing hardening response of this alloy at 80 h.…”