Twin roll casting of ZAX210 magnesium wire: Processing, microstructure, texture and mechanical properties

Abstract. Wires of magnesium alloys are appropriate candidates for applications as filler materials, as biomaterials due to their good biocompatibility and excellent mechanical properties but also as materials for joining applications, such as welding wires or screws. Twin roll casting (TRC) provides an innovative and efficient technology for the production of semi-finished wires with a good property profile. TRC of wire is a comparatively new technology that has so far only been performed at the Institute of Metal Forming at Technische Universität Bergakademie Freiberg, Germany. In recent studies, the process was combined with the promising calcium-containing Mg alloy ZAX210 (Mg-2Zn-1Al-0.3Ca). The wire was produced with an oval cross section under variation of twin roll casting speed in order to investigate the influence of twin roll casting speed (2.5 m/min to 4.5 m/min) on microstructure and texture evolution. Microstructure after TRC consists of fine dendrites and locally deformed microstructure. Twinning and small globular recrystallized grains can be detected as well. Furthermore, it can be observed that higher twin roll casting speeds (4.5 m/min) result in more pronounced formation of intermetallic phases and segregations but also in a higher amount of recrystallized grains, which arise due to dynamic recrystallization during twin roll casting. Texture analysis reveals the development of strong basal textures at lower (2.5 m/min) twin roll casting speed and weakened textures with prismatic character at increased twin roll casting speed of 4.5 m/min.