الفهرس 
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Abstract
Zinc-based alloys were manufactured and evaluated in the current study in order to develop a new biodegradable biomedical alloy for orthopaedic applications.Five different experimental alloys were created. They were made up of Zinc (Zn) as the balancing element, with Magnesium (Mg) added in 0.5, 1, 1.5, and 2 wt.% to make four degradable bone plate alloys for medical uses.To determine the suitability for usage as degradable bone plates, a compatibility assurance research was conducted. X-ray fluorescence (XRF) and X-ray diffractometer were used to determine the composition of all the produced alloys (XRD). The microstructure was examined by SEM (scanning electron microscope), EDS (energy dispersive spectrometer) and optical microscopy. Electrochemical degradation behaviour, immersion testin SBF (simulated body fluid) and mechanical tensile strength, compression strength and hardness were also tested. In vitro study was performed to select the most appropriate alloy to be inserted for human body and will be tested for cell adhesion.Good microstructure achieved and the highest hardness and wear resistance observed for 0.5 wt. % Mg alloy. Measurements indicated that the density decreases with increasing Mg ratio by 10.4% to 14%. The samples indicated high corrosion resistance in SBF and the degradation rate was low for all sampled ranged from
0.038 to 0.45 mm/year. Corrosion resistance was improved 71.68 % for 0.5 % Mg compared to pure Zn. Hardness and compression enhanced by addition of Mg, while the highest wear resistance achieved for 0.5 wt. % Mg. Compression and hardness tests were performed to determine the mechanical properties. In the compression tests, Zn-0.5 % Mg showed Tensile strength of Zn–Mg alloy were enhanced from 39 MPa for pure zinc to 320 MPa and 300 MPa for Zn–0.5 Mg alloy and Zn–2Mg alloy. This can be explained due to preparation process and presence of Mg + MgZn mixture in the structure. Compression strength of Zn–Mg alloy was enhanced from 65-75 MPa for pure zinc to 600 MPa and 620 for Zn–0.5 Mg alloy and Zn–2Mg alloy. No change in weight was detected for the different plates after immersion test.Zincalloy with 0.5 % Mg magnesium has the highest biocompatibility as it offers the highest corrosion resistance and lowest corrosion rate. In addition to excellent mechanical properties that approaches mechanical properties of cortical bone and exceeded, it is a suitable degradation material to be used for dental and bone plates applications.