Effect of Nd on the microstructure, mechanical properties and corrosion behavior of die-cast Mg–4Al-based alloy

Effects of Nd on the Microstructures, Mechanical Properties and in Vitro Corrosion Behavior of Cast Mg-1Mn-2Zn-<i>x</i>Nd Alloys

“…The presence of Cl ¹ ion accelerates the reaction by reacting with Mg(OH) 2 and forming a more resoluble MgCl 2 . 13) In the physiological environment, Mg and its alloys are relatively reactive metals, and they degrade to release H 2 gas and form corrosion products such as Mg(OH) 2 and calcium phosphates whilst increasing the pH of the physiological solution such as SBF or body fluid. The hydrogen release in the corrosion process retards the tissue healing, 13) so biodegradable Mg alloys should maintain the suitable degradation rate and mechanical integrity before the tissue healing.…”

“…13) In the physiological environment, Mg and its alloys are relatively reactive metals, and they degrade to release H 2 gas and form corrosion products such as Mg(OH) 2 and calcium phosphates whilst increasing the pH of the physiological solution such as SBF or body fluid. The hydrogen release in the corrosion process retards the tissue healing, 13) so biodegradable Mg alloys should maintain the suitable degradation rate and mechanical integrity before the tissue healing. The water solution including Cl ¹ ion such as SBF solution is often chosen as a corrosive test medium for Mg alloys and the volume of hydrogen evolution during immersion in the solution is measured to evaluate the corrosion behavior of Mg alloys.…”

“…Therefore, the results of the EIS also show that the corrosion resistance of the as cast alloys is much better than that of cast pure Mg and there is no great change in the EIS of all cast Mg alloys, which are in accord with the above polarization curves and suggest little influence of Nd content on the corrosion resistance of cast alloys. Other studies show that elements, Zn, Nd, and Mn can eliminate the harmful corrosive effects of impurity elements such as iron and nickel, and that Zn is more noble than Mg. 11,13,29) Those help to understand why the as-cast alloys have better corrosion resistance than cast pure Mg.…”

“…13,14) Previous study 15) has evaluated the vitro cytotoxicity of RE elements and suggested that dysprosium (Dy), gadolinium (Gd), yttrium (Y), europium (Eu), and neodymium (Nd) at a low concentration are suitable for biomedical application. Therefore, Mg-Mn-Zn-Nd alloys are expected to provide better mechanical and corrosion properties than Mg-Zn and MgMn-Zn alloys for biomedical application.…”

Effect of minor Gd on the corrosion behavior of AZ81 alloy

“…In the as-cast AZ series alloys, the addition of rare earth (RE) elements is believed to be a beneficial method to improve their corrosion resistance. Attempts have been made to change the microstructure of Mg-Al alloys by introducing thermally stable intermetallics through addition of special alloying elements and thereby improving its corrosion performance [6][7][8][9][10]. In this work, the influence of minor RE elements Gd additions on the corrosion behaviors of AZ81 Magnesium alloy is studied immersion in 0.5 and 3.5% NaCl solutions.…”