Effects of Phase Content and Evolution on the Mechanical Properties of Mg₉₅Y_2.5Zn_2.5 and Mg_93.1Y_2.5Zn_2.5Ti_1.6Zr_0.3 Alloys Containing LPSO and W Phases

Abstract

The effects of phase content and evolution on mechanical properties of the alloys are investigated by extruding Mg 95 Y 2.5 Zn 2.5 and Mg 93.1 Y 2.5 Zn 2.5 Ti 1.6 Zr 0.3 alloys with different original microstructures. The 18R-LPSO phase plays a decisive role in the strength of as-extruded alloys. The spherical W-MgYZn 2 phase enhances the deformability and ductility of the alloys. The dynamic recrystallization grains can be observed in all as-extruded alloys. However, the 14H-LPSO clusters and dynamic precipitates only form in the as-cast and T41-treated (solid-solution treatment at 530 C for 3 h with water cooling) alloys after extrusion. Based on synergistic effects of these phases mentioned above, the T41-treated Mg 93.1 Y 2.5 Zn 2.5 Ti 1.6 Zr 0.3 alloy exhibits good compressive mechanical properties after extrusion.

Microstructural Changes Caused by the Creep Test in ZK60 Alloy Reinforced by SiCp at Intermediate Temperature after KOBO Extrusion and Aging

“…By creating a kink band, the localized stress is released, reducing the internal energy to a minimum [ 43 ]. As the deformation continues, the dislocations in the kink band begin to arrange themselves, causing sub-boundaries to form, and the sub-grains begin to rotate to accommodate the microstructure, leading to the formation of new, smaller grains [ 44 ]. In addition to its increasing strength, this microstructure also exhibits improved ductility.…”