Effect of temperature on the microstructure and mechanical properties of Mg-Gd-Y-Zn-Zr alloy during the large height-to-diameter ratio upsetting and extrusion

In this paper, the Mg-9Gd-4Y-2Zn-Zr (wt. %) alloy was used as the research object. The effect of deformation temperature on the microstructure and mechanical properties of the alloy after one pass of large height-to-diameter ratio (5.5) upsetting and extrusion was studied. The microstructure evolution of one pass large height-to-diameter ratio upsetting and extrusion process was studied, which provided a theoretical basis for further study of large height-to-diameter ratio reciprocating upsetting and extrusion. The results show that with the increase of deformation temperature, the grain size decreases, the dynamic recrystallization rate increases, the granular b phase increases, the texture of the alloy tends to the typical extrusion texture, and the texture intensity increases gradually. With the increase in temperature, the mechanical properties of the alloy after upsetting and extrusion with a large height-to-diameter ratio increase. The ultimate tensile strength (UTS) of the alloy deformed at 460 degrees C increased to 355 +/- 6.7 MPa, the yield strength (YS) increased to 139 +/- 3.1 MPa, and the elongation (EL) was 17 +/- 0.7%. In the process of upsetting extrusion with the large height-to-diameter ratio, the initial discontinuous dynamic recrystallization (DDRX) changes to continuous dynamic recrystallization (CDRX).(c) 2023 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Automated summary

This paper investigates the microstructure and mechanical properties of Mg-9Gd-4Y-2Zn-Zr alloy after one pass of large height-to-diameter ratio upsetting and extrusion, and explores the effect of deformation temperature. The results show that with the increase in deformation temperature, the grain size decreases, the dynamic recrystallization rate increases, and the granular b phase increases, indicating a change in texture towards typical extrusion texture. The mechanical properties of the alloy, including ultimate tensile strength, yield strength, and elongation, increase with the increase in temperature.