Comparison of the microstructure and mechanical properties of a ZK60 alloy with and without 1.3 wt.% gadolinium addition

• Published in: Materials science & engineering. A, Structural materials : properties, microstructure and processing Structural materials : properties, microstructure and processing, 2006-10, Vol.433 (1), p.175-181
• Main Authors: He, S.M., Peng, L.M., Zeng, X.Q., Ding, W.J., Zhu, Y.P.
• Format: Article
• Language: English
• Subjects: Applied sciences; Cross-disciplinary physics: materials science; rheology; Elasticity. Plasticity; Exact sciences and technology; Magnesium alloys; Materials science; Mechanical properties; Mechanical properties and methods of testing. Rheology. Fracture mechanics. Tribology; Metals. Metallurgy; Mg–Zn–Gd–Zr alloy; Microstructure; Physics; Solid solution, precipitation, and dispersion hardening; aging; Treatment of materials and its effects on microstructure and properties; Wrought alloys
• ISSN: 0921-5093; 1873-4936
• DOI: 10.1016/j.msea.2006.06.063

The influence of 1.3 wt.% Gd on microstructure and mechanical properties of cast and hot-extruded ZK60 (Mg–6Zn–0.4Zr) alloy was studied in different conditions, including as-cast, cast-T4, cast-T6 and extruded-T5 and extruded-T6 at the extrusion temperatures of 623, 673 and 723 K. The results show that the addition of Gd leads to a considerable reduction of the age-hardening response and a small decrease of tensile yield strength (TYS) and ultimate tensile strength (UTS) in cast-T6 and extruded-T5 conditions, owing to the formation of Mg–Zn–Gd intermetallic compound which consumes some of Zn atoms in the matrix. However, the grain refinement caused by the addition of Gd is remarkable, which compensates partly for the loss of TYS and UTS due to the consumption of Zn in the matrix and improves the elongation of the alloy, especially at the elevated temperature.