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Theeffectsof annealing temperatureonthemicrostructure andtextureof theZr-Sn- Nb-Fe-Valloywerestudiedusingmetallographicobservation,second-phaseparticle(SPP) analysis,andtextureanalysis.Theresultsshowthatastheannealingtemperaturefollowing β-quenchingincreases, thegrain size in themetallographic structureof the Zr-Sn-Nb-Fe- Vsheet gradually increases, and theaverage size andsize distribution range of the SPPs gradually increase. The Zr-Sn-Nb-Fe-Vsheets at various annealing temperatures all have {0001} basaltexture,andthetexturestrengthofthesheetsatdifferentannealingtemperatures variessignificantly.

In this study, the effect of isothermal and isochronal aging is reported to investigate the precipitate evolution and recrystallization of N36 zirconium alloy after β-quenching. Two groups of samples were cut from the as-received sheet of N36 zirconium alloy and subjected to solution treatment and subsequent aging at 580, 640, and 700 °C for 40 and 600 min, respectively. Optical microscopy (OM), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), and electron backscattering diffraction (EBSD) were utilized to characterize the microstructure and second-phase particle (SPPs) evolution. Results show that the implemented quenching after solution treatment produces fine interlaced α-plates structure conserved inside prior β grain boundaries with 12 variant directions that follow Burger misorientation characteristics. After aging for a short time, initial α-plates conserve their shape and become softer, and SPPs spread along their boundaries. Recrystallizations are finished for specimens aged at a higher temperature or for a longer time. The recrystallized structure exhibits non-uniform grains and a random SPPs distribution. Despite the differences in morphology, some recrystallization grains retain the orientation feature from the initial α-plates. Hardness declines as temperature and time rise, and no hardness peak is seen. Roughness and wettability rise with increasing ageing temperatures.

In this paper, titanium dioxide (TiO2) nano-particles were synthesized by the sol-gel method by using Titanium tetrachloride (TiCl4) solution as precursor. The effects of calcination temperature were determined. The samples were examined using X-ray diffraction (XRD), scanning electron microscope (SEM) and Fourier-transform infrared spectroscopy (FT-IR) analysis. X-ray diffraction measurements showed that TiO2 nano-particles were polycrystalline with rutiles and anatase phases. The Surface morphological studies obtained from SEM micrographs. Particle size increased from 43 to 500 nm when calcination temperature was 500 oC. In the FT-IR spectra, the peaks observed below 700 cm−1 due to stretching and bending vibrations of Ti–O–Ti bond.

The main aim of this work is to enhance the surface protection of copper substrate from corrosion, by dipping process in nanocomposite PMMA-TiO2. Dipping method at constant dipping speed is applied to produce nanocomposite coat on copper substrate. The microstructure and morphology of the polymer nanocomposite coating, which includes different concentration of nanoparticles (NPs) of titanium dioxide filler (0, 1, 2 wt. %) as the reinforcing phase in PMMA matrix, was studied using SEM, AFM and FTIR. Corrosion measurement by Tafel polarization test was applied by using 3% NaCl solution. Finally, Vickers microhardness and contact angles were conducted on the nanocomposite coating surface. The results verified the formation of PMMA-TiO2 nanocomposite coating. The corrosion test illustrated that the lower corrosion rate was achieved at 2wt% TiO2 NPs. The results of the microhardness and contact angle showed that these properties depend heavily on the addition TiO2 NPs. with the best condition attained at the 2wt% TiO2 NPs.