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Journal of Materials Science and Nanotechnology | Volume: 3
March 20-21, 2019 | London, UK
Materials Science and Materials Chemistry
2
nd
International Conference on
Study on mechanical properties and corrosion resistance of Mg-Zn-Nd alloys as potential
biodegradable implants
Orly Hakimi
Ben-Gurion University of the Negev, Israel
M
g alloys are considered as potential structural materials
for biodegradable implants mainly due to their excellent
biocompatibility, degradation behavior in in vivo conditions and
adequate mechanical properties. However, their accelerated
corrosion rate in physiological environments may lead to
premature loss of mechanical integrity, gas embolism and
cytotoxic effects.
Here we characterized the corrosion behavior and mechanical
properties of a novel magnesium-zinc alloy, Mg-5%Zn-0.13%Y-
0.35%Zr with up to 3% Nd additions following a homogenizing
treatment and extrusion process, with regards to serving as a
biodegradable implant. Themicrostructural characteristicswere
examined by optical microscopy, scanning electron microscopy
(SEM), andX-ray diffraction analysis. The corrosionperformance
examination was carried out under in in vitro conditions,
including immersion testing, electrochemical analysis, and
stress corrosion cracking (SCC) assessments in terms of slow
strain rate testing (SSRT), all in PBS solution. The mechanical
evaluations included hardness and tensile examinations.
The obtained results clearly demonstrated an optimal
combination of strength and ductility for the new alloy at 2%Nd
concentration. This was attributed to an optimal concentration
of the secondary phase, W-phase (Mg
3
(Nd,Y)
2
Zn
3
), generated at
grain boundaries. The addition of different concentrations of
Nd to the base alloy, resulted in minor effect on the corrosion
resistance, nevertheless, the calculated corrosion resistance of
all tested alloys was within the range which can be considered
as suitable for biodegradable applications. Therefore it is
believed that the new alloy at 2% Nd concentration, Mg-5Zn-
2Nd-0.13Y-0.35Zr, can be considered as a potential candidate
for biodegradable implants.
e:
orlyha@sce.ac.il