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allied
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Journal of Biotechnology and Phytochemistry
Volume 1 Issue 3
Chemistry World 2017
Notes:
Page 46
November 13-15, 2017 Athens, Greece
7
th
World Congress on
Chemistry
Hydroxy Apatite Composite Coatings on Mg alloy for
Medical Applications
M Saremi, D Khazeni, S Nikosefat
and
M Ahangaran
University of Tehran, Iran
M
g and its alloys are important engineering materials
with widespread applications especially in aerospace
and automobile industries for their light weight and good
strength /weight ratio. Moreover, in recent years they have
been the focus of research for medical applications due to
their biocompatibility, biodegradability and nontoxicity. Mg
and Mg alloys are good candidates for use in orthopedic
applications as temporary implants because in addition to
the above mentioned properties they have also module of
elasticity near to the human bone. However such application
faces limitations due to high corrosion rate and H2 gas
formation. The corrosion of Mg alloy is desirable in temporary
implants but it should be controlled to retain its properties
during healing process of fractured bone. But H2 formation
is a considerable obstacle because it also interferes in healing
process.ThecorrosionofMgandMgalloys canbecontrolledby
applying different methods among them surface coating is the
most efficient and easy to perform. Hydroxyapatite is the most
suitable biocompatible ceramic material with composition
near to human bone which is used as coating in medical
applications. Application of biocompatible HA coating on
Mg alloys can reduce corrosion rate and consequently reduce
H2 formation. However, its brittle nature is a major problem
for use at load bearing sites of body implants. Moreover the
application of HA in orthopedic implants suffers from its
low toughness and poor wear resistance. This leads to the
focus on developing composite coatings with incorporation
of various biopolymers and reinforcing material to improve
its mechanical behavior. In our research works we have made
different composites of HA with Chitosan as a biopolymer,
CNT and Graphene. The composites were prepared and
applied on Mg alloy ( AZ31) by electrochemical cathodic
deposition using CNT or Chitosan as dispersion in the
electrolyte solution. In the next attempt graphene and HA
particles were dispersed in the electrolyte and the composite
of HA-Graphene deposited in an electrophoretic process.
he morphological studies showed uniform dispersion of
particles in the coating and further electrochemical tests using
Tafel polarization and EIS methods confirmed remarkable
improvement corrosion resistance of the composite coatings.
Nano indentation method was used to check the mechanical
behavior of the coating and the results showed considerable
improvement in mechanical properties.
Biography
Mohren Saremi is working at University of Tehran , Iran .He belongs to school
of metallurgy and materials engineering department
saremi@ut.ac.irM Saremi et al., J Biotech and Phyto 2017