Effects of deformation twinning on the mechanical properties of biodegradable Zn-Mg alloys

To satisfy the property requirements for biodegradable medical implants, Zn alloyed with low levels of Mg (≤0.8 wt%) has attracted increased research interest.In the present study, deformation twinning was observed in tensile tests and twinning appears to have an adverse impact on ductility.The profuse twinning in the as-cast Zn-Mg alloys accelerated crack growth in tension due to twinning impingement which caused local stress concentrations and initiates cracking.As-rolled Zn-Mg alloys have better ductility than their as-cast counterparts due to the inhibition of twinning by the refined Mg 2 Zn 11 intermetallic phase and the finer grain size.