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In this study, Inconel 625 powder was deposited on ASTM A592 steel substrate using laser cladding process. In order to optimize and predict the quality of the obtained coating, empirical-statistical method was used and the linear relationship between the coating geometries for each sample (angle, width, height, depth of penetration and dilution) and cladding parameters (power, powder feeding rate, and scanning rate) was obtained by the use of regression method. Using these relationships, a process map has been extracted to obtain the best quality for the cladding process. Hence, it is possible to obtain the optimal parameters of coating geometry and the main laser parameters for the deposition of Inconel 625 powder on the ASTM A592 steel substrate with minimum porosity and without crack.

In the current study, a set of urea–formaldehyde microcapsules (UFMs) were synthesized at different conditions via the in situ polymerization method. Encapsulation ability of the UFMs was studied by altering the synthesis parameters, such as formaldehyde to urea molar ratio (0.94, 1.88, 2.81), time (1, 4, 7h), temperature (25, 55, 85°C) and pH (3, 7, 11). The capsules were characterized by optical and electron microscopy (OM, SEM and TEM), particle size analysis (PSA), Fourier transform infrared spectroscopy (FTIR) and thermogravimetric/differential thermal analysis (TG/DTA). According to the results, for successful formation of UFMs, the pH value of the synthesis solution must be below 7 and the F/U molar ratio value must exceed 0.94. Effects of temperature and the pH value of the prepared solution were interdependent. To conclude, the results led to determination of the optimum UFM synthesis condition which presented the most effective formation of UFMs. The higher F/U molar ratio as well as higher curing temperatures in UFM-9, increased the UFMs degradation temperature. In order to further investigate the results, the synthesis of the optimized UFM (UFM-Opt.) was conducted, presenting the most effective development of UFMs.

To provide photocatalytic textiles, application of TiO2nanoparticles by surface modifications during the manufacturing process is known as a reliable choice. In this study, nitrogen-doped TiO2nanoparticles were synthesized by sol–gel route at two different water/triethylamine ratios and applied to the textiles which provides photocatalytic properties that unlike the conventional photocatalytic textiles, does not necessarily need UV radiations of high energy photons. N-doped TiO2nanoparticles were coated over textiles during the synthesizing process. Microstructure and morphology of synthesized N-doped TiO2nanoparticles were evaluated by XRD, PSA and SEM/EDS analysis. The results of XRD analysis indicated that the amorphous phase transformed slightly into an anatase crystallite without calcination at high temperature. The morphology confirmed that doping process had significant effect on the appearance of the synthesized nanoparticles and implied the effect of the presence of the N-doped source material on the morphology. The PSA analysis showed narrow distribution of about 15nm for diameter of synthesized N-doped TiO2nanoparticles. According to UV–vis spectra, the band gap energy was measured 2.98eV which exhibits high absorption in visible light range due to its low band gap energy. The results show that adding nitrogen increases the absorption wavelength of the N-doped TiO2nanoparticles and N-doped TiO2coated textiles shows super hydrophilic behavior examined by DSA analysis. The photodegradation of methylene blue (MB) over textiles was investigated under UV-radiation, visible light and dark conditions. Super-hydrophilicity and methylene blue photodegradation properties with the most homogenous nanoparticle distribution over textiles were achieved without utilization of UV radiation.