Improving the Ductility of Mg–Gd–Y–Zr Alloy through Extrusion and a Following Rolling

Abstract

Ductility of the Mg-8Gd-3Y-0.4Zr alloy is improved through extrusion and a following rolling performed on the as-cast alloy. Microstructure evolution, texture, and mechanical properties of the alloy are systematically investigated.The results indicate that the continuous-cluster distributed β phase particles observed in the as-cast alloy are fragmented and dissolved during the plastic deformation. Nearly random texture, improved ductility (by 60%), and strength (by 23%) are obtained. To uncover the formation mechanism of the texture, uniaxial compression on the alloys with and without homogenization (to obtain alloys without and with β phase) is performed. The microstructure characterization reveals that β phase impedes the grain boundary immigration, resulting in the nearly random texture, thereby improving the mechanical properties, especially the ductility of the alloy.

Constitutive Modeling of Hot Deformation Behaviors and Processing Maps of Mg–4.83Gd–2.36Nd–0.21Zr Alloy

“…[23,24] The hot working process, especially extrusion, is often used to manufacture high-strength and high-ductile Mg alloys. [25,26] It is critical to optimize the processing parameters for achieving the desired postdeformation properties based on the deformation behavior and microstructure evolution. As is known, the constitutive model and processing map have been extensively used to study the flow behavior and optimal forming windows.…”

Microstructure and Texture Evolution during Twin-Roll Casting and Annealing of a Mg–6.8Y2.5Zn–0.4Zr Alloy (WZ73)

“…Magnesium alloys are often associated with low strength and insufficient ductility. However, research efforts in the development of new magnesium alloys have shown that by adding rare earth elements, alloys with excellent mechanical properties can be obtained [1]. In some alloying systems-such as Mg-Y-Zn-so-called LPSO (long period stacking ordered) structures occur which contribute significantly to improving the strength and ductility of these alloys [2,3].…”