Improvement of mechanical properties of extruded AZX912 magnesium alloy using high-temperature solution treatment

For achieving flame-retardant AZX912 magnesium alloy with superior mechanical properties, cast ingots were solution-treated at different temperatures of 420–525 °C prior to extrusion at 280 °C. With increasing solution treatment temperature, brittle Al 2 Ca intermetallic compound changed from a network-like morphology to a spheroidized shape, with an increase in hardness and became unbroken during extrusion. As the solution treatment temperature increased, cracking of Al 2 Ca particles during tensile deformation tended to be restricted due to hardening and spheroidizing behaviors, and tensile elongation of extruded alloys significantly enhanced from 11.2 to 19.2%. High mechanical strength was maintained with an improvement in ductility when increasing the solution treatment temperature up to 510 °C. The extruded alloy solution-treated at 510 °C exhibited a superior balance between mechanical strength and ductility, with a high ultimate tensile strength of 367 MPa and a good elongation of 16.8%.