Achieving exceptional improvement of yield strength in Mg-Zn-Ca alloy wire by nanoparticles induced by extreme plastic deformation

The size and distribution of second phase particles have an important influence on the mechanical properties of Mg alloys and further determine their application. In this study, extreme plastic deformation was employed to control the microstructure and tune the corresponding mechanical properties of Mg-Zn-Ca alloy. The uniformly dispersed nanoparticles (average diameter of-14.3 nm) could be successfully introduced into the Mg-Zn-Ca alloy wire after cold drawing with an area reduction of-99.8%, and the high yield strength of-285 MPa was obtained. When compared to the as-extruded alloy with yield strength of-171 MPa, the exceptional improvement in yield strength (-114 MPa) for the Mg-Zn-Ca alloy wire is mainly attributed to the formation of nanoparticles. Moreover, the Mg wire also exhibited a good ductility of-11.8%. The results indicate that extreme plastic deformation can enable a refined microstructure to enhance the mechanical properties of Mg-Zn-Ca alloys.