A High-Strength and High-Elongation Soluble Mg-Gd-Y-Zn-Zr-Cu Alloy for Fracturing Tool Fabrication

Abstract

Developing soluble magnesium alloys with excellent comprehensive mechanical properties is key for shale oil/gas fracturing tools. In this study, Mg-7.3Gd-3.0Y-1.0Zn-0.2Zr-xCu alloys were prepared via direct cooling casting and extrusion. They exhibited a tensile yield strength (TYS) of over 325 MPa and an elongation (EL) of over 13.8%, mainly due to their fine grain size (≈50 µm) from dynamic recrystallization at the relatively low extrusion temperature (400 °C). As Cu content rose, corrosion rate increased, yet mechanical properties stayed stable. The Mg-7.3Gd-3.0Y-1.0Zn-0.2Zr-1.2Cu alloy showed the best properties: a TYS of 349.6 MPa, an EL of 14.3%, and a corrosion rate of 783.7 mm/year in 3 wt% KCl at 93 °C.

Keywords: Soluble Mg-Gd-Y-Zn-Zr-Cu Alloy, Yield Strength, Elongation, corrosion