Mechanical and Corrosive Properties of Two Magnesium Wires: Mg4Gd and Mg6Ag

摘要

The mechanical and corrosive properties of two Magnesium wires are studied in the field of microhardness, tension-, compression- and 3-point-bending tests, corrosion and its influence on the mechanical properties. Due to recrystallization during their complex forming processes (casting, extrusion, wire drawing), both wires show a fine grained microstructure resulting in high strength and ductility. However, the ductility is mostly evaluated by 3-point bending and compression; due to the notch effect in the clamp area, the maximum tensile strength and elongation under tension cannot be measured. Both alloys show a tensile-compressive yield asymmetry. Even RE-elements are known to reduce this asymmetry, the Mg-Gd alloy shows 100 MPa higher strength in tension than compression. The asymmetry of the Mg-Ag wire is similar. Overall the wires show very high strength and hardness, Mg6Ag slightly higher compared to Mg4Gd. Strong pitting corrosion is found and reduces strongly the tensile and bending strength.