Browsing by Author "Çavdar P.S."
Now showing 1 - 5 of 5
Results Per Page
Sort Options
Item Ultra-high frequency induction welded process of reinforcement steel(Slovenska Akademia Vied, 2016) Çavdar P.S.Induction welding is developing as an alternative method to welding processes. In this study, two different welding processes were applied. One of them was ultra-high frequency induction welding (UHFIW), the other was electrode welding (EW). Additionally, S420 reinforcement steels (RS) were rapidly welded by ultra-high frequency induction system using a current at a frequency of 900 kHz and 2.8 kW power capacity. These steels are generally used in the construction of buildings. S420 RS were welded at 1100°C by induction for 5 min under an atmosphere environment. Alternatively, S420 RS were welded by the electrode. Mechanical properties and microhardness measurements were investigated for both processes. The results of the experimental studies were compared with each other.Item Analysis of artificial aging with induction and energy costs of 6082 Al and 7075 Al materials(CSIC Consejo Superior de Investigaciones Cientificas, 2019) Taştan M.; Gökozan H.; Çavdar P.S.; Soy G.; Çavdar U.In the study, 6082 Al and 7075 Al samples were subjected to a solution taking place at 580 °C for 1 min using ultrahigh frequency induction heating system (UHFIHS) and water was supplied at the end of the process. Artificially aging was then carried out at 190 °C for 2, 4, 6 and 8 min. In both applications, heating was carried out using an induction system with a frequency of 900 kHz and a power of 2.8 kW. For these aluminum series and shapes, induction heating and heat treatment costs in different shapes are calculated. In addition, the hardness values obtained from artificially aged 6082 Al and 7075 Al samples at 190 °C for 10 h were compared with conventional methods after 5 h at 540 °C for 5 h. As a result, the hardness values of 6082 Al samples, which were obtained in 10 h by conventional methods, were obtained by artificial aging for only 8 min using induction system. © 2019 CSIC.Item Cost analysis of T6 induction heat treatment for the aluminum-copper powder metal compacts(International Institute for the Science of Sintering (IISS), 2020) Taştan M.; Gökozan H.; Çavdar P.S.; Soy G.; Çavdar U.This work compares an energy cost and an energy consumption results of the 4 wt.% cupper mixed aluminum based powder metal (PM) compacts processing under induction or furnace heating. Total power and energy consumptions and total energy costs per kilogram and compact have been analyzed. T6 precipitation heat treatment applications have been applied with two different methods, one with 2.8 kW, 900 kHz ultra-high frequency induction heating system (UHFIHS), other with 2 kW chamber furnace. In the first method, Al-Cu PM compacts have been heated by induction at 580 °C in one minute and then cooled down by water. Afterwards, the samples have been heated 170, 180, 190 and 200 °C respectively for artificial ageing and cooled naturally. In the second treatment, unlike the first study, Al-Cu PM compacts are heated by chamber furnace at 540 °C in 5 hours and cooled by water. Then PM compacts are artificially aged at 190 °C in 10 hours with same furnace. During both processes, energy and power consumptions for each defined process have been measured. Optimum heat treatment of the induction is determined. The cheaper energy cost is obtained by the induction heat treatment. © 2020 Authors. Published by association for ETRAN Society.Item Heat Treatment of 2024 and 5083 Aluminum Materials by Induction, a Competitive Method, and Cost Analysis(Springer, 2021) Çavdar U.; Taştan M.; Gökozan H.; Soy G.; Çavdar P.S.In the study, 2024 Al and 5083 Al bulk samples were heated using two different methods, induction and conventional heat treatment. Using these methods, the processing cost and time analysis for both materials were performed. 5083 Al material cannot be heat-treated. However, to evaluate differences in the production cost of induction by changing the components of aluminum, the same procedures were applied to 5083 Al material. In both aluminum series, square, cylindrical, and hexagonal shapes were processed, and the effect of sample shape variations on cost was evaluated. The heat treatment was performed in a conventional kiln of 2 kW. Al materials were heat-treated for 5 h at 540 °C, and water was suddenly supplied. Then they were left in the kiln at 190 °C for 10 h for artificial aging. Al samples were heat-treated in the same way at 590 °C for 1 minute in the 900 kHz ultra-high frequency induction heating system (UHFIHS), which was fed with instant water. The samples were then artificially aged at four different heating durations varying between 2 and 8 minutes using the induction system. As a result of examining the production time and cost of both methods, it was found that the heat treatment of 2024 Al samples by induction was much more advantageous. Furthermore, when Al samples were heated by induction, shape differences and main alloy elements significantly affected power consumption values. © 2020, Springer Science+Business Media, LLC, part of Springer Nature.Item NUMERICAL ANALYSIS OF PULSATING FORCED CONVECTION IN A BACKWARD-FACING STEP FLOW SUBJECTED TO NANOFLUIDS(Gheorghe Asachi Technical University of Iasi, Romania, 2021) Çavdar P.S.; Solmaz B.; Selimefendigil F.; Yurddaş A.The numerical investigation of pulsating forced convection in a backward-facing step flow using water-based nanofluids has been presented. This study is performed for different Reynolds numbers (based on the step height) in the range of 10 and 200, different inlet velocity and different Strouhal number. The effects of water-based nanofluids, which contain Al2O3 (Aluminium oxide) and Cu (Copper) nanoparticles with volume fractions ranging from 1% to 5%, on the heat transfer were determined. All numerical solutions were evaluated by using the Finite Volume Method of Computational Fluid Dynamics. The effects of related parameters as Reynolds number and pulsating frequency on the fluid flow and heat transfer characteristics have been numerically analyzed. Increasing the Cu nanoparticle volume ratio gets the heat transfer better than of all. © 2021 Gheorghe Asachi Technical University of Iasi, Romania. All rights reserved.