Mechanical properties and corrosion behavior of biodegradable Mg-Cu alloys

Mechanical properties and in vitro corrosion behavior of Mg-Cu alloys in the simulated body fluid solution were investigated. Copper addition led to grain refinement and formation of alpha-Mg/Mg2Cu eutectics, resulting in the best combination of mechanical properties for the as-cast Mg-0.5Cu alloy, for which the values of the yield stress, ultimate tensile strength, total elongation, and tensile toughness were obtained as 71 MPa, 164 MPa, 5.8%, and 7.5 MJ/m3, respectively. Hot deformation by extrusion led to fine grain sizes via dynamic recrystallization and breaking up the eutectics. Accordingly, the extruded Mg-0.1Cu alloy showed tensile toughness of similar to 30 MJ/m3 and good corrosion resistance; while Mg-1.2Cu alloy with a distinct protective surface layer was also considered as a viable alternative for biomedical applications.