الفهرس 
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Abstract
The present study investigates the use of four bathes I , II, III and IV in electrodeposition on two different alloys Mg - 1% Zn and Mg - 6% Zn.
The experimental results obtained and their interpretation is included in chapter III.
Chapter III deals with electro plating for the four bathes containing Ca(NO3)2 as the calcium ion source, di-ammonium di-hydrogen phosphate NH4H2PO4 as the phosphate ion source, sodium nitrate NaNO3 to increase conductivity, hydrogen peroxide (H2O2) to erase at pot 1.4V. Coat Bath I Bath II Bath III Bath IV Composition CaNO3 9.90 g/l 9.90 g/l 11.00 g/l 11.00 g/l NH4H2PO4 2.87 g/l 4.00 g/l 2.87 g/l 4.00 g/l NaNO3 1.27 g/l 1.27 g/l 1.27 g/l 1.27 g/l Na3PO4 2.00 g/l 2.00 g/l 2.00 g/l 2.00 g/l H2O2 20.00 ml/l 20.00 ml/l 20.00 ml/l 20.00 ml/l
In part one the electrodeposition was studied of the four bathes on Mg-1%Zn alloy. The surface morphology of the coat have flake- like structure with grain size 8.50, 7.10, 5.30 and 2.19 for HA,HAP, HACa and HAPCa respectively.
FTIR analysis shows the presence of hydroxyl, nitrate, phosphate, hydrogen phosphate groups.
X-ray diffraction pattern indicated that the structure of the coat in case of bath I, II, III, and IV is monoclinic calcium phosphate dihydrate, hexagonal magnesium, calcium oxide, magnesium oxide and magnesium hydroxide.
The elements percentage of the constituents in the coat of the implants is shown from EDAX analysis. The elements are Mg, P, Zn, Ca and O.
Then test the protection of the coated alloys in the SBF immediately and after different periods of immersion two and four weeks.
The Potentiodynamic polarization of the implants uncoated and coated by the different four bathes are studied in simulated body fluid. The results show that IV › III › II › I.
Also study the protection of the coated alloys after immersion in simulated body fluid for two and four weeks.Potentiodynamic polarization measurements show that the coated alloys have more corrosion resistance than the uncoated ones.
Also as the immersion time of the coated alloys increase in SBF, the corrosion protection increase following the sequence
IV › III › II › I.
In part two the electrodeposition was studied of the four bathes on Mg- 6%Zn alloy. The surface morphology of the coat have flake- like structure with grain size 7.91, 5.87, 5.13 and 2.05.
FTIR analysis show the present of hydroxyl, nitrate, phosphate, hydrogen phosphate groups.
X-ray diffraction pattern indicated that the structure of the coat incase of the four bathes is monoclinic calcium phosphate dihydrate, hexagonal magnesium, calcium oxide, magnesium oxide and magnesium hydroxide.
The elements percentage of the constituents in the coat of the implants is shown from EDAX analysis. The elements are Mg, P, Zn, Ca and O.
Then we test the protection of the coated alloys in the SBF immediately and after different periods of immersion two and four weeks.The Potentiodynamic polarization of the implants uncoated and coated by the different four bathes are studied in simulated body fluid. The results show that IV › III › II › I.
Also we study the protection of the coated alloys after immersion in simulated body fluid for two and four weeks.
Potentiodynamic polarization measurements show that the coated alloys have more corrosion resistance than the uncoated ones.
Also as the immersion time of the coated alloys increase in SBF, the corrosion protection increase following the sequence IV › III › II › I.