Microstructure and Mechanical Properties of Mg-5Li-3Al-1Zn Alloys with Y Addition Fabricated by Hot Extrusion
摘要
Mg-5Li-3Al-1Zn (wt.%) alloys with varing Y addition (0-0.20 wt.%) were produced through vacuum melting and hot extrusion. The microstructure and mechanical properties of the alloys were analyzed using optical microscopy, scanning electron microscopy, x-ray diffractometry, electron backscatter diffraction and tensile tests. Results showed that extrusion refined and homogenized the microstructure. The Mg-5Li-3Al-1Zn-0.1Y alloy exhibited the best mechanical properties, with a tensile strength of 275 MPa, yield strength of 150 MPa, and elongation of 24%. This alloy also had the smallest average grain size and dispersed Al2Y particles. Furthermore, Y addition altered the c-axis deviation, enhancing non-basal slip and improving plasticity.