The Taguchi procedure is an important method for obtaining high quality without increasing the cost in the optimization of the process parameters. In the Taguchi procedure, the orthogonal planes of the maximum effects of the controllable process parameters and the minimum effects of the uncontrollable process parameters were used. In this study, B4C, SiC, and FeCrC powders were alloyed on the surface of an AISI 430 ferritic stainless steel by plasma transfer arc (PTA) welding. The abrasive wear of the various specimens was measured by the mass loss at a load between 10 and 16 N using SiC abrasive paper with a 60 and 240 mesh and over distances between 20 and 30 meters. The effects of the parameters with respect to the lowest wear behavior as an important criterion were optimized by the lowest-the best control characteristic of the Taguchi method. The results were analyzed by graphical methods.

Оттиски доступны непосредственно от издателя Фотокопирование разрешено только в соответствии с лицензией 2015 ИМФ (Институт металлофизики им. Г. В. Курдюмова НАН Украины) Напечатано в Украине.

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Being widely used in automotive, machinery, aviation and aerospace industry, solid-sate friction welding was applied in this study. AISI 420 martensitic stainless steel, being difficult to be joined by using fusion welding methods, was joined by friction welding. During the welding process, three rotational speeds (R) of 700, 1000 and 1300 rpm were used and other parameters such as friction pressure (Fp), friction time (Ft), upsetting pressure (Up) and upsetting duration (Ud) were kept constant. After the welding process, a torsion test was performed with these samples. The torsion angle (Ta) – torque (T) graphics of the samples were evaluated. Additionally, the fracture surface of the samples was examined by using SEM. As a result, it was observed that the AISI 420 steel was welded without problems by using friction welding. During the torsion tests, the samples fractured outside the welded joint zones. Thus, it was concluded that torsional strength of the welded joints was high.

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In this study, martensitic stainless steel (AISI 420) that is difficult to bond by fusion welding methods joined by friction welding. During welding, three different rotational speeds were used and parameters such as friction pressure, friction time, forging pressure and forging time were kept constant. After the welding process, welding interfaces were examined by SEM. Then these parts were subjected to microhardness test. Welded parts were subjected to tension test for determine the mechanical strength of welded joints. After investigations, AISI 420 martensitic stainless steel was observed that without a problem can be welded by friction welding.

In this study, pure CdO and CdO‐CuO nanopowders with different dopant concentrations are synthesized by the hydrothermal method. Structural properties of the nanopowders are characterized by X‐ray diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR), morphological properties and elemental analyses are characterized by Field Emission Scanning Electron Microscopy (FESEM), optical properties are characterized by UV–vis spectroscopy, and electrical properties are characterized by the current–voltage technique. XRD data show that nanopowders are polycrystalline and crystallinity decreases with the doping concentration. In the analysis of FESEM images, it can be concluded that the morphology of the particles is shaped as needle‐like, spherical‐like, and randomly oriented nanorods forms from the cube form. Also, by joining those nanorods, spherical‐like microstructures occur, and while the dopant concentration increases, echinus‐like forms are obtained. The energy bandgap of the nanopowders decreases with an increased dopant concentration of CuO. It is observed that the dopant concentration of CuO also changes the electrical properties.