Publication details

Authors: Wu, K.; Dogan, O. N.; Velikokhatnyi, O. I.; Kumta, P. N. 
Title: A CALPHAD study on the thermodynamic stability of calcium-, zinc-, and yttrium-doped magnesium in aqueous environments 
Type: Journal Article 
Publisher: Materials Science and Engineering B-Advanced Functional Solid-State Materials 
Year: 2011 
Volume: 176 
Issue: 20 
Start Page: 1727 
End Page: 1732 
DOI: 10.1016/j.mseb.2011.04.016 
Abstract: Magnesium has attracted the attention of the biomaterials community as a potential biodegradable metallic candidate for use in stents and orthopedic applications. Alloying of Mg with metals such as Ca, Y and Zn, etc., to form alloy precursors is important to optimize its corrosion rate in electrolytic and aqueous environments to understand the alloy response in body fluid environments. In the current study, the chemical reactions of Mg-Me alloys (Me = Ca, Y, and Zn) with pure water have been investigated using the CALPHAD technique. A qualitative agreement between CALPHAD and first-principles results has been obtained. The CALPHAD method has also been employed to study the reactions of Mg alloys in the human blood fluid environment. The effects of alloying elements and compositions on the reaction enthalpies, reaction products, amount of gas release and gas compositions as well as the pH of the fluids have been systematically discussed and reported. (C) 2011 Elsevier B.V. All rights reserved. 
Keywords: biodegradable mg-alloys, heat of reactions, calphad, thermodynamics, enthalpy of formation, free energy of formation, stimulated adhesion, orthopedic implants, osteoblastic cells, alloys, biomaterials, mechanisms