To obtain high strength for near-rapid solidification (NRS) magnesium alloys, the microstructures and mechanical properties of the Mg94Zn2.4Y3.6 (at%) alloys, which were prepared by ordinary and injection copper mold casting (ICMC), respectively, were investigated comprehensively. It has been shown that the microstructure of ICMC Mg94Zn2.4Y3.6 alloy possesses the far-away-from equilibrium feature of NRS materials, which is composed of refined α-Mg grains with supersaturated Y and Zn, fine network-like long-period stacking-order (LPSO) phases and a few of Mg24Y5 particles. The interface between LPSO phase and α-Mg matrix is semi-coherent with the orientation relationship of α//[112¯0]LPSO, (101¯0)α//(0002)LPSO. The ICMC alloy exhibits enhanced mechanical properties with the ultimate tensile strength and elongation up to 355 MPa and 7% at room temperature, respectively, and with the ultimate tensile strength of 302 MPa at 150 °C. It can be concluded that the strengthening mechanisms of this ICMC alloy are attributed to the grain refinement, the solid solution effect, the secondary phase strengthening and the crystalline boundaries strengthening.
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Condensed Matter Physics
- Mechanics of Materials
- Mechanical Engineering