Microstructure and Mechanical Properties in a Gd-Modified Extruded Mg-4Al-3.5Ca Alloy

In the present study, microstructure and mechanical properties of a new Mg-4Al-3.5Ca-2Gd (AXE432) alloy are investigated. The as-cast AXE432 consists α-Mg, C14 (Mg2Ca), C36((Mg, Al)2Ca) phases. After heat treatment at 480 °C for 8 h, with fine lamellar structure changes from narrow stripes to micro-scale particles, part C36 dissolve into α-Mg matrix, many short needle-shaped C15 (Al2Ca) phase precipitating in primary a-Mg grains. extruded temperature as high 420 exhibits refined dynamically recrystallized (DRXed) grain sizes less than 1.5 ± 0.5 μm strong {0001}<101¯0> basal texture maximum intensity 5.62. A complex combination effects size, texture, second-phase strain hardening results balanced properties, tensile yield strength (TYS), ultimate (UTS), elongation (El), compressive (CYS), (UCS) 331.4 2.1 MPa, 336.9 3.8 16.1 2.3%, 270.4 1.6 MPa 574.5 12.4 respectively.