-In this study, lead-free (Na0.5K0.5)NbO3-BiTiO3 ceramics were fabricated by a conventional mixed oxide method. Structural and electrical properties of lead-free (Na0.5K0.5)NbO3 ceramics with the variation of BiTiO3 were investigated. The results of X-ray diffraction analysis showed a typical polycrystalline perovskite structure without presence of the second phase in all specimens. Sintered density increased with an increasing of BTO and the specimen added with 0.07 mol% of BiTiO3 showed the maximum value of 97.8%. Average grain size decreased and densification increased with an increasing of BiTiO3 contents. The electromechanical coupling factor of the 0.01 mol% BiTiO3 doped NKN specimens was 0.32. Dielectric constant, dielectric loss and Curie temperature of the 0.07 mol% BiTiO3 doped NKN specimens were 1185, 0.145% and 400 o C, respectively.

La7.33Bi2(SiO4)6O2 specimens were fabricated by standard solid-state synthesis route for solid oxide electrolytes. The calcined powders exhibited uniform particles with a mean particle size of about 28 μm. The room-temperature structure of La7.33Bi2(SiO4)6O2 specimens was analyzed as hexagonal, space

Arc plasma flow between electrodes has been investigated in several studies. However, in the industrial field, arc plasma flow between electrodes is hindered by interfering materials such as filler metal in arc welding, substrates in chemical vapor deposition, and powders in sintering. Therefore, in this study, high temperature arc plasma flow analysis via three obstruction structure shapes was performed to understand the inter-electrode interference phenomena. COMSOL Multiphysics was used for the analysis; COMSOL interface such as electric field, magnetic field, heat transfer, and fluid flow (laminar flow) was applied and Multiphysics such as plasma heat source and temperature coupling were considered. The temperature and velocity of the arc plasma were determined and the energy transfer between the electrodes was analyzed. We confirmed that the concave shape has a lower average heat flux than the other shapes, with the arc pressure evenly distributed in the anode. It is concluded that the concave shape can reduce the flow of the plasma from the anode and obtain even distribution of the arc plasma in the radial direction.