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In this study, various amounts of clay nanoparticles and titan nanoparticles (1, 3 and 5% wt.) were introduced into a vinyl ester resin matrix by high shear mixer. The influence of these nanoparticles on the mechanical properties (tensile strength, tensile modulus, flexural strength, flexural strength and fracture toughness) is investigated. To investigate the structure of nanocomposites, X-ray diffraction (XRD) and transmission electron microscopy (TEM) tests are done. The XRD test shows that the structure of clay-vinyl ester nanocomposites is exfoliated. The results of tensile, flexural and fracture toughness experiments show that clay is better than titan in the improvement of the mechanical properties. Clay- vinyl ester nanocomposite with 1% wt. of clay has the better mechanical properties than others samples.

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Ultrasonic Assisted Magnetic Abrasive Finishing (UAMAF) is the combination of magnetic abrasive finishing (MAF) and ultrasonic vibrations to finish the surfaces in nanometer scale. In this work, the experimental setup for UAMAF was prepared to finish inner surface of tube workpiec. By using experimental setup, the effect of experimental parameters such as ultrasonic vibrations, mesh number, the type of abrasives (SiC and diamond) and finishing time has been investigated on the changes in the surface roughness of AL6061 tube workpiece. The experimental results showed that the use of ultrasonic vibrations has a significant effect on reducing the surface roughness. The changes in surface roughness increases with the mesh number from 90 to 800 and finishing time from 30s to 5 min. Among two types of abrasives, diamond showed the best performance in finishing. Optical microscopy images showed that the dominant finishing mechanism in MAF for coarse grains (with mesh size of 90 and 120) is two body and for fine grains (with mesh size of 220, 400 and 800) is three body. In UAMAF for both of the coarse and fine grains the dominant finishing mechanism is three body.