Novel Ultrafine-Grain Mg-Gd/Nd-Y-Ca Alloys with an Increased Ignition Temperature

• Published in: Materials Vol. 16; no. 3; p. 1299
• Main Authors: Šašek, Stanislav, Minárik, Peter, Stráská, Jitka, Hosová, Klára, Veselý, Jozef, Kubásek, Jiří, Král, Robert, Krajňák, Tomáš, Vojtěch, Dalibor
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 03.02.2023; MDPI
• Subjects: Aircraft; Calcium; Equal channel angular pressing; flammability resistance; Gadolinium; Grain boundaries; Grain size; High strength alloys; Ignition temperature; Investigations; magnesium; Magnesium alloys; Magnesium base alloys; Magnesium industry; Mechanical properties; microstructure; Scanning electron microscopy; Software; Specialty metals industry; Spectrum analysis; Tensile deformation; ultrafine-grain; Ultrafines; United States > US; Germany; magnesium; microstructure; ultrafine-grain; flammability resistance; mechanical properties
• ISSN: 1996-1944; 1996-1944
• DOI: 10.3390/ma16031299

Two novel ignition-resistant magnesium alloys, Mg-2Gd-2Y-1Ca and Mg-2Nd-1Y-1Ca, were prepared in the ultrafine-grain condition by equal channel angular pressing (ECAP). In addition, four commercial alloys-AZ31, AX41, AE42 and WE43-were prepared similarly as a reference. The microstructure, mechanical properties and ignition temperature were thoroughly investigated. Both novel alloys exhibited a mean grain size of ~1 µm and dense distribution of small secondary phase particles. The mechanical strength measured by the tensile deformation test showed that the novel alloys are much stronger (~290 MPa) than all commercial alloys except WE43. However, Ca segregation into the grain boundaries caused a significant decrease in ductility (<6%). The ignition temperature of the novel alloys (~950 °C) was considerably improved by the presence of Gd/Nd, Y and Ca. This study showed that both novel alloys exhibit high strength and high ignition temperature in the ultrafine-grain condition.