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Fatigue properties of Ti-6Al-4V (TC4) subjected to 0.9% physiological saline solutions were presented in this paper. The ultrasonic fatigue test method has been used to investigate the very high cycle fatigue properties of commercial titanium alloy TC4 with the microstructure of tramsformed lamellar dipped into 0.9% physiological saline solution prior to testing. Three estimated times have been decided for subjecting at 37 °C, such as 24 hours, 2 weeks and 4 weeks. The results show that physiological saline solution treatment makes a little influence on the ultrasonic fatigue life of TC4. The slope of S-N curve decreases as the dipping time increases. Dipping tests for three estimated times also have been performed. When TC4 has been dipped into physiological saline solution for 4 weeks, homogeneous white points have been observed on specular facet specimen. And in the fracture surface of which has been dipped for 4 weeks, new inclusion sized 5-10 µm in the crack initiation has been observed. The fractography pictures show the fracture to be transcrystalline plastic. Cracks are initiated because of the subsurface inclusion and the facet slip of α-phase.

The possibilities of movement and electrochemical reduction of fibroin macroions in the presence of tricalcium phosphate ions in the form of a nanocoating during electrolysis have been studied. The manifestation of a non-Newtonian flow of a mixture of macroions and ions in a shear flow, the conditions for their electrochemical reduction in the form of a nanocoating with uniform morphology, and thickness on the electrode surface are revealed. It was found that the excess ions in the mixture and the uneven relief of the electrode surface contribute to the formation of a nanocoating with an inhomogeneous and uneven thickness.