Manganese and zinc were selected as alloying ele- ments to develop a Mg-based ternary alloy for biomedical applications, taking into account the good biocompatibility of these metals. The microstructures of Mg–Zn–Mn alloys con- taining 0.5 or 1.0 mass% of manganese and 1.0 or 1.5 mass% of zinc were investigated by scanning electron microscopy coupled with energy dispersive X-ray spectroscopy. Their corrosion properties were assessed by means of potentiody- namic polarization and electrochemical impedance spectros- copy measurements performed in Ringer’s physiological solution that simulates bodily fluids. All tested samples are two-phase alloys formed by a Mg-based matrix, consisting of a Mg–Zn–Mn solid solution, and a Mg–Zn binary phase. The electrochemical results show an improvement of the corro- sion behavior of the investigated alloys with increasing Zn and Mn content. This is attributed to the formation of a par- tially protective Mg(OH)2 surface film whose protective capa- bilities are increased by the alloying elements. The reduced influence of the Mg–Zn intermetallic compound on the corro- sion rate of Mg–Zn–Mn alloys in the presence of a partially protective surface layer can be ascribed to an increasing re- sistance between the Mg–Zn–Mn solid solution and the sec- ond phase, thereby decreasing the effective driving force for microgalvanic corrosion. Owing to its highest corrosion protective ability, the Mg–1.5Zn–1Mn alloy is a promising candidate for the development of degradable implants, such as screws, plates, and rods.
Microstructure and in vitro degradation performance of Mg–Zn–Mn alloys for biomedical application / Rosalbino F.; De Negri S.; Scavino G.; Saccone A.. - In: JOURNAL OF BIOMEDICAL MATERIALS RESEARCH. PART A. - ISSN 1549-3296. - ELETTRONICO. - 101A:3(2013), pp. 704-711. [10.1002/jbm.a.34368]
|Titolo:||Microstructure and in vitro degradation performance of Mg–Zn–Mn alloys for biomedical application|
|Data di pubblicazione:||2013|
|Digital Object Identifier (DOI):||http://dx.doi.org/10.1002/jbm.a.34368|
|Appare nelle tipologie:||1.1 Articolo in rivista|