In the present study, Al 2 O 3 -Ti coated on TiAl 6 V 4 alloy used electrophoretic deposition (EPD) method to improve the corrosion resistance and biocompatibility. Electrophoretic deposition process was performed at 90 s and constant voltage of 50 V in various compositions of 30, 50, and 70 wt% of Al 2 O 3 . After deposition, samples were dried at room temperature and then the coated samples were sintered at 1050 8C for 4 h. Scanning electron microscope and X-ray diffraction analysis were employed to investigate the microstructure and phase analysis of the coatings. Moreover, the behavior of the coated samples was investigated by using electrochemical impedance spectroscopy and polarization tests. The results show that the Al 2 O 3 -Ti composite coatings sintered at an inert gas (argon) atmosphere reveals a uniform, dense coating, which includes the composition of Ti and Al oxide phases. Evaluation of electrochemical test in simulated body fluid represents the improvement of the corrosion resistance of the coated sample in comparison to uncoated TiAl 6 V 4 sample. Moreover, the 50 wt% of Al 2 O 3 composite coated sample revealed the highest corrosion resistance among the coated samples due to a uniform and more stable phase composition in comparison to other coated samples.

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Densification, grain growth, magnetic and dielectric properties of sintered Li–Zn ferrite (Li0.3Zn0.4Fe2.3O4) doped with nano silicon dioxide (10 nm) were investigated. The density and microstructural results revealed that increasing the nano-SiO2 content resulted in lower density and higher porosity at sintering temperatures below 1 000 °C, whereas at higher temperatures, this led to higher density and grain growth. In addition, nano-SiO2 content greater than 2 wt.% resulted in more reduction in porosity and had no effect on grain growth. Moreover, the highest density and the maximum induction (Bs = 380 mT) were obtained for the sample containing 2 wt.% nano-SiO2 and sintered at 1 100 °C for 1.5 h, in comparison with undoped samples. Furthermore, the variation of magneto-dielectric properties as a function of frequency were explained according to Koop's theory and electron hopping between the Fe+ 2 and Fe+ 3 ions.