Phase Formation, Microstructure and Mechanical Properties of Mg67Ag33 as Potential Biomaterial

The phase and microstructure formation as well as mechanical properties of the rapidly solidified Mg67Ag33 (at. %) alloy were investigated. Owing to kinetic constraints effective during rapid cooling, the formation of equilibrium phases is suppressed. Instead, the microstructure is mainly composed of oversaturated hexagonal closest packed Mg-based dendrites surrounded by a mixture of phases, as probed by X-ray diffraction, electron microscopy and energy dispersive X-ray spectroscopy. A possible non-equilibrium phase diagram is suggested. Mainly because of the fine-grained dendritic and interdendritic microstructure, the material shows appreciable mechanical properties, such as a compressive yield strength and Young's modulus of 245 +/- 5 MPa and 63 +/- 2 GPa, respectively. Due to this low Young's modulus, the Mg67Ag33 alloy has potential for usage as biomaterial and challenges ahead, such as biomechanical compatibility, biodegradability and antibacterial properties are outlined.

Automated summary

The investigation on rapidly solidified Mg67Ag33 alloy showed that it mainly consists of oversaturated Mg-based dendrites with appreciable mechanical properties. Therefore, the alloy has potential for usage as biomaterial, but challenges such as biomechanical compatibility, biodegradability and antibacterial properties need to be addressed.