Konca, Erkan
Loading...
Name Variants
Konca E.
K., Erkan
K.,Erkan
Konca, E.
Erkan, Konca
E., Konca
Konca, E
E.,Konca
Konca, Erkan
Konca,E.
K., Erkan
K.,Erkan
Konca, E.
Erkan, Konca
E., Konca
Konca, E
E.,Konca
Konca, Erkan
Konca,E.
Job Title
Doçent Doktor
Email Address
erkan.konca@atilim.edu.tr
ORCID ID
Scopus Author ID
Turkish CoHE Profile ID
Google Scholar ID
WoS Researcher ID
Scholarly Output
17
Articles
10
Citation Count
92
Supervised Theses
3
17 results
Scholarly Output Search Results
Now showing 1 - 10 of 17
Book Part Citation Count: 0Effect of electroplating parameters on internal stress in ni-m0s2 composite plating(Wiley Blackwell, 2013) Güler,E.S.; Konca,E.; Karakaya,I.; Metallurgical and Materials Engineering[No abstract available]Article Citation Count: 16Investigation of the tribological behaviour of electrocodeposited Ni-MoS2 composite coatings(inderscience Enterprises Ltd, 2017) Guler, Ebru Saraloglu; Konca, Erkan; Karakaya, Ishak; Metallurgical and Materials EngineeringComposite electroplating of solid lubricants in a metal matrix is an effective way to lower coefficient of friction (COF) and improve wear resistance of surfaces in sliding contact. In this work, Ni-MoS2 composite coatings were deposited on AISI 304 stainless steel substrates by electroplating from Watts bath containing suspended MoS2 particles and their tribological behaviour was studied. The effects of MoS2 particle concentration (5, 10 and 30 g/l), MoS2 particle size (1.440 and 5.156 mu m), pH (2, 3 and 4), current density (3.8, 4.8 and 5.8 A/dm(2)) and the surfactant (sodium lignosulfonate, SLS) concentration (0.3 and 1 g/l) on the tribological behaviour were investigated using a ball-on-disc tribometer at ambient conditions. Lower current density, smaller particle size and higher concentration of MoS2 decreased COF. While increasing the surfactant concentration decreased the COF, its friction lowering effect was much more pronounced at relatively lower concentrations of MoS2 in the electrolyte.Conference Object Citation Count: 0EFFECT OF ELECTROPLATING PARAMETERS ON "HER" CURRENT DENSITY IN Ni-MoS2 COMPOSITE PLATING(Minerals, Metals & Materials Soc, 2012) Guler, Ebru Saraloglu; Karakaya, Ishak; Konca, Erkan; Metallurgical and Materials EngineeringNickel composites with co-deposited insoluble, solid lubricant particles such as MoS2 have been reported to reduce friction. It is known that hydrogen evolution reaction (HER), competes with nickel deposition. The influence of the electroplating parameters and their interaction effects on the peak current density for HER were studied by fractional factorial design. The parameters and their ranges were; MoS2 concentration (0-30 g/l), temperature (30-50 degrees C), pH (2-4) and surfactants (0-1 g/l). Electrodeposition processes were carried out from a typical Watts bath containing leveler, wetting agent and brightener by using a potentiostat. The peak currents (I-p) were extended to higher values and the peaks on linear sweep voltammograms became noticeable by increasing the scan rate from 20 mV/s to 100 mV/s over the range 0 to 2.5 V. The peak current densities (i(p)) for each experimental route were determined by fractional factorial design for three types of mineral processing surfactants; sodiumlignosulfonate (SLS), depramin-C (DC) and ammoniumlignosulfonate (ALS) using Minitab program [1]. Adding MoS2, decreasing temperature and increasing pH has decreasing effect on peak current density for all surfactants. ALS and DC have increasing effect whereas SLS has descending effect on peak current.Conference Object Citation Count: 1Effect of electroplating parameters on internal stress in Ni-MoS 2 composite plating(2013) Saraloǧlu Güler,E.; Konca,E.; Karakaya,I.; Metallurgical and Materials Engineering[No abstract available]Conference Object Citation Count: 0Effect of electroplating parameters on "HER" current density in Ni-MoS2 composite plating(Minerals, Metals and Materials Society, 2012) Güler,E.S.; Karakaya,I.; Konca,E.; Metallurgical and Materials EngineeringNickel composites with co-deposited insoluble, solid lubricant particles such as MoS2 have been reported to reduce friction. It is known that hydrogen evolution reaction (HER), competes with nickel deposition. The influence of the electroplating parameters and their interaction effects on the peak current density for HER were studied by fractional factorial design. The parameters and their ranges were; MoS2 concentration (0-30 g/l), temperature (30-50°C), pH (2-4) and surfactants (0-1 g/l). Electrodeposition processes were carried out from a typical Watts bath containing leveler, wetting agent and brightener by using a potentiostat. The peak currents (I p) were extended to higher values and the peaks on linear sweep voltammograms became noticeable by increasing the scan rate from 20 mV/s to 100 mV/s over the range 0 to 2.5 V. The peak current densities (ip) for each experimental route were determined by fractional factorial design for three types of mineral processing surfactants; sodiumlignosulfonate (SLS), depramin-C (DC) and ammoniumlignosulfonate (ALS) using Minitab program [1]. Adding MoS2, decreasing temperature and increasing pH has decreasing effect on peak current density for all surfactants. ALS and DC have increasing effect whereas SLS has descending effect on peak current.Article Citation Count: 1ÖSTENİTLEME SICAKLIĞININ EN-GJS-600-3 KÜRESEL GRAFİTLİ DÖKME DEMİRİN ÖSTEMPERLENME DAVRANIŞINA ETKİLERİNİN ARAŞTIRILMASI(2020) Konca, Erkan; Tur, K Zım; Metallurgical and Materials Engineering; Department of Metallurgical and Materials EngineeringBu çalışmada östenitleme sıcaklığının EN-GJS-600-3 (GGG-60) küresel grafitli dökme demirinöstemperlenme davranışına etkisi araştırılmıştır. Y bloklarına dökülen % 0,5 Cu alaşımlı EN-GJS-600-3küresel grafitli dökme demirden çıkarılan numuneler kullanılarak iki farklı östenitleme sıcaklığı (850 ve950°C) ve iki farklı östemperleme sıcaklığının (290 ve 320°C) dört ayrı kombinasyonunda östemperlemedeneyleri yapılmıştır. Östemperleme deneyleri sonrası numunelerin sertlik ölçümleri, çekme testleri ve içyapı incelemeleri gerçekleştirilmiştir. Her iki östemperleme sıcaklığında da 950°C’de östenitlenmişnumunelerde 850°C’de östenitlenmiş numunelere göre daha yüksek sertlik, akma ve çekme dayanımıdeğerlerine ulaşılmıştır. Bu sonuçlar, 950°C’de yapılan östenitlemenin 850°C’ye göre östenit matris içindehem daha çok karbonun çözünmesini hem de östenitin daha iri taneli olmasını sağlayaraköstemperlenmeye daha elverişli östenit yapısı oluşturabilmesiyle ilişkilendirilmiştir.Article Citation Count: 23Effect of Electrodeposition Parameters on the Current Density of Hydrogen Evolution Reaction in Ni and Ni-MoS2 Composite Coatings(Esg, 2013) Gueler, E. Saraloglu; Konca, E.; Karakaya, I.; Metallurgical and Materials EngineeringNickel composites with co-deposited insoluble, solid lubricant particles such as MoS2 have been reported to reduce friction. It is known that hydrogen evolution reaction (HER), competes with nickel deposition. The influence of the parameters and their interaction effects on the peak current density of HER during the electrodeposition of Ni and Ni-MoS2 composite coatings were studied by fractional factorial design. The parameters and their ranges studied were; MoS2 particle concentration (0-30 g/l), temperature (30-50 degrees C), pH (2-4) and two surfactants, namely; ammoniumlignosulfonate (ALS) and depramin-C (DC) (0-1 g/l). Electrodeposition processes were carried out from a typical Watts bath containing leveler, wetting agent and brightener by using a potentiostat. The peak current densities (i(p)) were extended to higher values and the peaks on linear sweep voltammograms became noticeable by increasing the scan rate from 20 mV/s to 100 mV/s over the range of 0 to 2.5 V. The peak current densities (i(p)) of HER for each experimental route were determined by fractional factorial design for two mineral processing surfactants; ammoniumlignosulfonate (ALS) and depramin-C (DC) using a statistical analysis software named Minitab [1]. Adding MoS2, decreasing temperature and increasing pH had decreasing effects on the peak current density of HER regardless of the surfactant used. On the other hand, the surfactants increased the peak current density.Article Citation Count: 23Effects of Alloying Elements (Mo, Ni, and Cu) on the Austemperability of GGG-60 Ductile Cast Iron(Mdpi, 2017) Konca, Erkan; Tur, Kazim; Koc, Erkin; Metallurgical and Materials Engineering; Department of Metallurgical and Materials EngineeringThe interest in austempered ductile irons (ADI) is continuously increasing due to their various advantageous properties over conventional ductile irons and some steels. This study aimed to determine the roles of alloying elements Ni, Cu, and Mo, on the austemperability of GGG-60 ductile cast iron. Two different sets of GGG-60 (EN-GJS-600-3) samples, one set alloyed with Ni and Cu and the other set alloyed with Mo, Ni, and Cu, were subjected to austempering treatments at 290 degrees C, 320 degrees C, and 350 degrees C. A custom design heat treatment setup, consisting of two units with the top unit (furnace) serving for austenitizing and the 200 L capacity bottom unit (stirred NaNO2-KNO3 salt bath) serving for isothermal treatment, was used for the experiments. It was found that austempering treatment at 290 degrees C increased the hardness of the Ni-Cu alloyed GGG-60 sample by about 44% without causing a loss in its ductility. In the case of the Mo-Ni-Cu alloyed sample, the increase in hardness due to austempering reached to almost 80% at the same temperature while some ductility was lost. Here, the microstructural investigation and mechanical testing results of the austempered samples are presented and the role of alloying elements (Mo, Ni, and Cu) on the austemperability of GGG-60 is discussed.Article Citation Count: 17Investigation of the tribological behaviour of electrocodeposited Ni-MoS2 composite coatings(Inderscience Publishers, 2017) Güler,E.S.; Konca,E.; Karakaya,I.; Metallurgical and Materials EngineeringComposite electroplating of solid lubricants in a metal matrix is an effective way to lower coefficient of friction (COF) and improve wear resistance of surfaces in sliding contact. In this work, Ni-MoS2 composite coatings were deposited on AISI 304 stainless steel substrates by electroplating from Watts bath containing suspended MoS2 particles and their tribological behaviour was studied. The effects of MoS2 particle concentration (5, 10 and 30 g/l), MoS2 particle size (1.440 and 5.156 μm), pH (2, 3 and 4), current density (3.8, 4.8 and 5.8 A/dm2) and the surfactant (sodium lignosulfonate, SLS) concentration (0.3 and 1 g/l) on the tribological behaviour were investigated using a ball-on-disc tribometer at ambient conditions. Lower current density, smaller particle size and higher concentration of MoS2 decreased COF. While increasing the surfactant concentration decreased the COF, its friction lowering effect was much more pronounced at relatively lower concentrations of MoS2 in the electrolyte. Copyright © 2017 Inderscience Enterprises Ltd.Article Citation Count: 24Effect of electrodeposition parameters on the current density of hydrogen evolution reaction in Ni and Ni-MoS2 composite coatings(2013) Saralog̀lu Güler,E.; Konca,E.; Karakaya,I.; Metallurgical and Materials EngineeringNickel composites with co-deposited insoluble, solid lubricant particles such as MoS2 have been reported to reduce friction. It is known that hydrogen evolution reaction (HER), competes with nickel deposition. The influence of the parameters and their interaction effects on the peak current density of HER during the electrodeposition of Ni and Ni-MoS2 composite coatings were studied by fractional factorial design. The parameters and their ranges studied were; MoS2 particle concentration (0-30 g/l), temperature (30-50°C), pH (2-4) and two surfactants, namely; ammoniumlignosulfonate (ALS) and depramin-C (DC) (0-1 g/l). Electrodeposition processes were carried out from a typical Watts bath containing leveler, wetting agent and brightener by using a potentiostat. The peak current densities (ip) were extended to higher values and the peaks onlinear sweep voltammograms became noticeable by increasing the scan rate from 20 mV/s to 100 mV/s over the range of 0 to 2.5 V. The peak current densities (ip) of HER for each experimental route were determined by fractional factorial design for two mineral processing surfactants; ammoniumlignosulfonate (ALS) and depramin-C (DC) using a statistical analysis software named Minitab [1]. Adding MoS2, decreasing temperature and increasing pH had decreasing effects on the peak current density of HER regardless of the surfactant used. On the other hand, the surfactants increased the peak current density. © 2013 by ESG.
