Effects of Al and Y Addition on Microstructures and Mechanical Properties of As‐Cast Mg–14Li Based Alloy

Abstract

In this study, effects of Al and Y contents on microstructural evolutions and mechanical properties of the as‐cast Mg–14Li alloy are investigated. The results show that Mg–14Li–xAl (x = 1, 2, 3 wt%) alloys are characterized by predominantly single β–Li and MgLiAl2 phases. Slight refinement of β–Li grains is obtained with the increasing of Al content. The increased Al addition greatly improves the hardness, ultimate tensile strength, and yield strength of the Mg‐14 base alloy, accompanied by a significant reduction in ductility. Meanwhile, with addition of minor Y (0.5 wt%) addition leads to the introduction of homogeneous distribution of Al2Y particles in the Mg–14Li–3Al alloy, which plays a positive role in the strength enhancement. However, the uneven distribution of apparently coarsed Al2Y particles contributes to a significant reduction in tensile strength as the Y content is increased up to 1 wt%.

Effects of Al, Y, and Zn Additions on the Microstructure and Mechanical Properties of Mg−3Li Alloy

“…The preferential formation of Al 2 Y is attributed to the large difference in electronegativity between Al and Y elements. Al 2 Y is a thermally stable phase with a high melting point (up to 1485 °C), [ 22 ] which can be formed before the solidification of the α‐Mg matrix. On the one hand, Al 2 Y can provide the nucleation points of the matrix; on the other hand, it can hinder the growth of grains.…”

“…The characteristic of SAED is consistent with the stacking faults (SFs),[21] so it is judged that the parallel thin strip-like phase is not the second phase but SFs.The preferential formation of Al 2 Y is attributed to the large difference in electronegativity between Al and Y elements. Al 2 Y is a thermally stable phase with a high melting point (up to 1485 C),[22] which can be formed before the solidification…”

High‐Cycle Fatigue Behavior of Deep Cryogenic–Elevated Temperature Cycling Treated Sand‐Cast Mg–6Gd–3Y–0.5Zr Alloy

“…Due to the low density, good machinability, high specific strength, and good damping capacity, magnesium alloys have received widespread attention as a recyclable structural material in the automotive and aerospace fields. [1][2][3][4] Compared with conventional aluminum and magnesium alloys, Mg-Gd-Y alloys have been reported to exhibit higher strength not only at ambient temperature, but also at elevated temperature and to display remarkable corrosion resistance and creep resistance. [5][6][7][8] Recently, abundant works have been conducted in relation to the Mg-Gd-Y system.…”

Microstructural Evolution and Mechanical Properties of As‐Cast and As‐Extruded Mg–14Li Alloy with Different Zn/Y and Zn/Gd Addition

“…Therefore, it has great significance to improve the performance of the superlight Mg–14Li‐based alloy. [ 13–16 ]…”