Effect of Hot Extrusion on the Microstructure, Mechanical Properties, and Corrosion Behavior of Mg-11Li-3Al-2Zn-1.5Nd-0.2Zr Alloy

摘要

The microstructure, mechanical properties, and corrosion behavior of Mg-11Li-3Al-2Zn-1.5Nd-0.2Zr alloy before and after hot extrusion were studied. The results show that both as-homogenized and as-extruded alloys consist of beta-Li, AlLi, MgLi2Al, and NdAl3 phases. The ultimate tensile strength and elongation of as-extruded alloy are 149.86 MPa and 42.33%, respectively, which are higher than those of as-homogenized alloy (132.99 MPa and 19%). The as-extruded alloy shows a better corrosion resistance with a lower hydrogen evolution rate and a higher charge transfer resistance. The improvement of mechanical properties and corrosion resistance of Mg-11Li-3Al-2Zn-1.5Nd-0.2Zr alloy after hot extrusion are as a result of the grain refinement and the uniform distribution of crumbled intermetallic phases.