Mechanical behaviour and bio-corrosion performance of Zn-Cu-Mn based alloys for biomedical applications

The mechanical behaviour and bio-corrosion properties of Zn-1.2Cu-xMn (x=0.2, 0.4, and 0.6wt%) alloys was investigated in this study. The alloy compositions were produced via liquid metallurgical processing and characterized using scanning electron microscopy (SEM), and X-ray diffractometry (XRD). The mechanical properties were evaluated using hardness, tensile properties, fracture toughness measurement while corrosion studies in Hank's solution was used to access the bio-corrosion behaviour. The results show that the tensile test of the studied Zn alloys increased in ultimate strength from 79.52 to 112.65MPa, fracture toughness from 6.99 to 7.71 MPam^1/2 and hardness from 10.59 to 18.80 Hv, but with significant reduction in ductility from 5.21% to 3.63%. The improved mechanical properties were attributed to solid solution and second phase strengthening. The alloys presented appropriate in vitro degradation rates of 25-73μm/year in Hank's solution. Based on the results demonstrated by the studied Zn-Cu-Mn alloys with suitable mechanical properties and ideal degradation behavior, it is projected as a promising candidate for cardiovascular stent applications.