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In this paper, we report effective, useful and environmental compatible ultrasound method for the synthesis of zeolite-Y. Then, the prepared product was composed with palladium nanoparticles by sonication treatment. The prepared zeolite Y-Pd nanoparticles was used as catalyst in Suzuki-Miyaura coupling of aryl halides (Ar-X, X = I, Br, Cl, F) with phenylboronic acid. Based on our studies, the prepared zeolite Y-Palladium nanoparticles revealed a high catalytic performance in Suzuki-Miyaura coupling reaction so that aryl fluoride can even react with phenylboronic acid by utilizing this catalyst. The advantages of the use of this catalyst in Suzuki-Miyaura coupling reaction are green solvent, short reaction time, high yields, ligandless and recyclable. Structure and morphology of the synthesized zeolite-Y and zeolite-Y-Palladium nanoparticles were characterized by FT-IR (Fourier transform infrared), XRD (X-ray diffraction), SEM (Scanning electron microscopy), TEM (Transmission electron microscopy), EDX (Energy dispersive analysis of X-ray), BET (Brunauer Emmett Teller) and ICP-MS (Inductively coupled plasma mass spectrometry).

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In this research, the effect of boron nitride (BN) reinforcement particles on microstructure and mechanical properties of Al6061-T6 surface layer composites prepared by friction stir processing (FSP) were investigated. Microstructural changes of surface composites were examined by optical microscope (OM). Also, scanning electron microscope (SEM) was utilized to evaluate dispersion of reinforcement particles. The results illustrated that the BN reinforcement particles were uniformly dispersed in the nugget zone after 4 passes of FSP. It was also determined that the micro-hardness was enhanced from 97 Hv to 157 Hv due to the pining effect of hard BN reinforcement particles and reducing the grain size of processed zone from 312.65 μm to 12.09 μm. The results also indicated that increasing the number of FSP passes increased hardness, as well as the yield strength (σ y ), tensile strength (σ UTS ) and elongation (%E) of specimens. Corrosion resistance of Al6061/BN surface composite was examined by electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization techniques. Results showed that Al6061/BN surface composite presented better corrosion behavior in comparison to Al6061-T6 and FSPed Al6061-T6 without BN reinforcement particles.

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