Atmospheric RE-free Mg-based bulk metallic glass with high bio-corrosion resistance

In this work, a rare earth (RE) free Mg69Zn27Ca4 bulk metallic glass (BMG) of diameter 1.5 mm was successfully fabricated by the injection casting method using recycled materials in atmospheric air. Without using high vacuum conditions, high purity starting materials and expensive rare earth materials, the findings of the work are of significance in reducing the cost and improving the manufacturability of BMGs. The results of the uniaxial compression tests further showed that there were no obvious differences between BMGs prepared under high vacuum or in atmospheric environment. The electrochemical polarization measurements in simulated physiological media revealed that the atmospheric Mg69Zn27Ca4 BMG manifested much lower passive current densities, higher pitting potential and a wider passive region than those of ZK60 and pure Mg alloys. The findings not only present Mg69Zn27Ca4 BMG as low cost material for potential biomedical applications, but also provide new insights into understanding of the effects of oxygen on glass formation.