Yazarlar
- Çolak, Murat(6)
- Dispinar, Derya(2)
- Şüküroğlu, Ebru Emine(2)
- Betül Ege(1)
- Colak, M.(1)
- Coşar, Mehmet(1)
- Dispinar, D.(1)
- Durmus, M.(1)
- Durmuş, Melek(1)
- Gavgali, M.(1)
- Gavgali, Mehmet(1)
- Güngör, Kadir(1)
- Kaya, Sinan(1)
- Kaymaz, Irfan(1)
- Köse, Sami(1)
- Teke, Çağatay(1)
- Uslu, Emin(1)
- Yalçin, Önder(1)
- Şensoy, Abdullah Tahir(1)
Yayınlar
- MakaleAçık Erişim2026Scopus SJRQ2Investigation of the Effect of Niobium Addition on Fluidity and Mechanical Properties in Casting of Aluminum Alloys
Çolak, Murat; Yalçin, Önder
Aluminum and its alloys are important engineering materials widely used in the defense industry, industrial production, and machinery industry. Depending on the increase in quality expectations from aluminum casting alloys, castings are made with different alloy element additions. In the study, the effects of Nb addition to A356 aluminum alloy on casting properties were investigated with experimental studies. The Nb addition rate in the alloy was determined as 0.03%, 0.06% and 0.1%. Four-channel fluidity mold with varying section thicknesses, spiral fluidity mold and mechanical test mold were used in casting experiments. As a result, with the addition of Niobium, an increase in maximum tensile strength and % elongation was observed, while a decrease in fluidity properties was observed.
AtıfScopus4WoS5OpenAlex4
İncele - MakaleAçık Erişim2026Scopus SJRQ2Experimental and Modeling Study of Fluidity in Ductile Iron (GGG40)
Coşar, Mehmet; Şüküroğlu, Ebru Emine; Güngör, Kadir; Çolak, Murat
Ductile irons (spheroidal graphite cast irons, SGI) are widely used in automotive and energy systems due to their high strength, ductility, and excellent machinability. The casting quality of these alloys largely depends on the flow and filling behavior of the molten metal, namely its fluidity. In this study, the effects of pouring temperature, filling time, and metallurgical quality on the fluidity of GGG40 ductile iron were investigated through both experimental and numerical approaches. Experimental trials were conducted at pouring temperatures of 1350 °C, 1400 °C, and 1450 °C; metallurgical quality levels of 10%, 50%, and 90%; and filling times of 5 s and 10 s. The fluidity lengths were measured and statistically evaluated. The results revealed that increasing the pouring temperature and metallurgical quality significantly improved fluidity, while shorter filling times allowed the molten metal to travel longer distances before solidification. Modeling studies performed using a commercial casting simulation software showed strong correlation with the experimental data. Microstructural examinations indicated that higher pouring temperatures and improved metallurgical quality led to a more homogeneous distribution of graphite nodules and an increased ferrite fraction in the matrix. The findings provide valuable insights into the influence of process parameters on the fluidity behavior of ductile iron and offer critical design data for enhancing casting quality and productivity in industrial foundry applications.
AtıfScopus1İncele - MakaleAçık Erişim2025Scopus SJRQ3Effect of Fe Amount on Microstructure and Fluidity of A356 Alloy
Durmus, M.; Dispinar, D.; Gavgali, M.; Colak, M.
The most important factor affecting the production of quality parts with aluminum alloys is the quality of molten metal. One of the determining factors in molten metal quality is the minimization of trace impurity elements in the alloy. One of the most harmful impurities among these elements is Fe, and its amount is a determining factor in its negative effect. It is known that Fe negatively affects the quality of aluminum, causing a decrease in mechanical properties. Most of the Fe in the alloy forms intermetallic from needle-like to complex Chinese-script structures. In this study, carbon steel and stainless-steel rods were immersed in the liquid metal at casting temperatures of 700°C and 750°C in A356 aluminum casting alloy and were subjected to diffusion for 1, 2 and 5 hours. Subsequently, a 4-channel flow test mold with various section thicknesses was used. All samples were measured by measuring the liquid metal advance distances of all sections in mm. Then, microstructure analyses were performed on the obtained sections. As a result, it is observed that as Fe diffusion increases, liquid metal advancement distances decrease and Fe intermetallics form in the microstructure. © The Author(s) 2025. Open Access. This article is licensed under a Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made.
- MakaleAçık Erişim2025Scopus SJRQ2Evaluation of Fe Content on the Fluidity of A356 Aluminum Alloy by New Fluidity Index
Durmuş, Melek; Dispinar, Derya; Gavgali, Mehmet; Uslu, Emin; Çolak, Murat
Elements that are deliberately added to aluminum alloys or are incorporated into the alloy later depending on the production process affect the final product properties. In addition, liquid metal cleaning is important in minimizing undesirable elements. Considering the production process, one of the most harmful impurities that is likely to pass into the alloy via diffusion for aluminum is the element, Fe. It is known that this is due to the fact that although Fe is highly soluble in liquid aluminum and its alloys, it has very little solubility in solids. Depending on the Fe content, mechanical properties, porosity and fluidity properties are affected in aluminum alloys. In this study, stainless and carbon steel rods were dipped into the melt at 700 °C and 750 °C for 1, 2 and 5 h. Castings were performed before and after degassing. Four-channel fluidity mold with different section thickness was used in the trials. Additionally, microstructure characterization was performed under varying casting conditions. Fluidity Index was proposed which is a single value measured from all fluidity values in different sections. When the results were examined, it was determined that the diffusion material, holding time, casting temperature and liquid metal cleanliness had an effect on the fluidity. Due to the increase in diffusion time, a decrease in fluidity was observed in both carbon steel and stainless steel. It was found that fluidity was significantly reduced when using stainless steel.
AtıfScopus14WoS14OpenAlex15İncele - MakaleAçık Erişim2025Scopus SJRQ2Investigation of the Effects of Filling Speed, Casting Temperature and Metallurgical Quality on Fluidity of Lamellar Graphite Cast Iron at Different Section Thicknesses
Köse, Sami; Çolak, Murat; Şüküroğlu, Ebru Emine
In this study, the fluidity properties of the alloy were investigated at different casting temperatures, different section thicknesses, and varying casting parameters of lamellar graphite cast iron materials. To achieve our goal, we utilized sand molds that were created with specific parameters including pouring temperature, metallurgical quality, section thickness, and fluidity test model. These molds were used for casting. Thus, the effect of fluidity properties in changing casting conditions and liquid metal advance distances at determined section thicknesses was investigated. Modeling was carried out with FlowCast casting simulation software by determining the liquid metal advance distance depending on the section thickness in the castings made in sand molds under changing casting conditions. The fluidity and advance distance of the liquid metal was determined comparatively with experimental and modeling techniques under the changing casting conditions in the parameters determined in this study. When the outcomes were examined; it was observed that different liquid metal advance distances occur at different cross-section thicknesses depending on the changing conditions.
AtıfScopus8WoS8OpenAlex7İncele - MakaleAçık Erişim2022Scopus SJRQ2Determination of flow distance of the fluid metal due to fluidity in ductile iron casting by artificial neural networks approach
Teke, Çağatay
Ductile irons (DIs) have properties such as high strength, ductility, and toughness, as well as a low degree of melting, good fluidity, and good machining. Having these characteristics make them the most preferred among cast irons. The combination of excellent properties, especially in DI castings with a thin section, make it an alternative for steel casting and forging. But in the manufacture of thin-section parts, fluidity characteristics need to be improved and the liquid metal must fill the mold completely. The fluidity of liquid metal is influenced by many factors depending on the casting processes such as material and mold properties, casting temperature, inoculation, globalization, and grain refinement. In this study, an artificial neural network (ANN) model has been developed that allows for determining the flow distance of the liquid metal in the sand mold casting method under changing casting conditions of DI. Thus, the flow distance was estimated depending on the cross-sectional thickness during the sand casting under changing casting conditions. The experimental parameters were determined as casting temperature, liquid metal metallurgy quality, cross-sectional thickness, and filling time. Filling modeling was performed with FlowCast software. When the results were examined, it was seen that the developed ANN model has high success in predicting the flow distances of the liquid metal under different casting conditions. The calculated coefficient of determination (R2) value of 0.986 confirms the high prediction performance of the model.
AtıfScopus4WoS4İncele - Derleme MakaleAçık Erişim2021Scopus SJRQ2Investigation of the Effect of Inoculant and Casting Temperature on Fluidity Properties in the Production of Spheroidal Graphite Cast Iron
Çolak, Murat; Kaya, Sinan
Working with liquid metal makes the casting method very advantageous, but also presents some difficulties. One of the common challenges in the casting process is that the liquid metal may not fill the mold cavity completely. This is mainly due to the contact of the liquid metal with the mold surface in the mold cavity, the high heat transfer coefficient of the mold material, and the undercooling and solidification of the liquid metal during liquid movements. For this reason, the fluidity of the liquid metal is important for robust casting production. The fluidity is affected by many factors such as mold properties, casting temperature, and alloying elements. In this study, it is aimed to investigate the fluidity characteristics of GGG60 alloy. For this purpose, the effects of casting temperature, different inoculants, and different inoculant quantities were used in the new mold design, which has different cross-sectional thicknesses. The distance of the alloy in the cavities was also compared with FlowCast Casting simulation software.
AtıfScopus8WoS8OpenAlex9İncele - MakaleYalnız künye2020Scopus SJRQ2Investigating the Optimum Model Parameters for Casting Process of A356 Alloy: A Cross-validation Using Response Surface Method and Particle Swarm Optimization
Şensoy, Abdullah Tahir; Çolak, Murat; Kaymaz, Irfan; Dispinar, Derya
This study aimed to determine the optimal casting parameters for the maximum fluidity of A356 alloy. Gravity die cast method was used. For this purpose, central composite design (CCD) was performed. The input parameters and their limits for the trial design were selected as pre-heating temperature (100–400 °C), casting temperature (680–760 °C), and cross-sectional thickness (1–10 mm). Using the CCD-based simulation results of the feed distance, a highly correlated full-quadratic regression equation was obtained with the highest R2 (0.99), which then was used as the objective function for the particle swarm optimization (PSO) process. The highest value of the response parameter, flow distance, reached up to 491.19 mm when the input parameters were selected as 400 °C, 760 °C and 10 mm, respectively. The sensitivity analysis has shown that the most effective parameter on the fluidity is the cross-sectional thickness. The response surface method (RSM)-based optimization results have been also validated using the PSO method. Although the higher temperatures have been found to result in better fluidity, there may be some drawbacks to working at higher temperatures such as energy cost and mould life. To determine the optimum input parameters, the RSM model suggested in this study can be modified for any type of casting process. Moreover, especially for a complex-shaped part, the manufacturer can be advised regarding operating conditions such as pre-heating and casting temperatures.
AtıfScopus11WoS9OpenAlex13İncele - Yüksek Lisans TeziAçık Erişim2019Okuma güçlüğünün giderilmesinde akıcı okuma stratejilerinin etkisi
Betül Ege
Araştırmanın amacı, okuma güçlüğünün giderilmesinde akıcı okuma stratejilerinin etkisini incelemektir. Araştırmanın amacı doğrultusunda okuma güçlüğünün giderilmesi için eko (yankılayıcı) ve tekrarlı okuma stratejileri bu araştırmada birlikte kullanılmıştır. Araştırma sürecinde şiir türü metinler ile uygulama yapılmıştır. Bu araştırma tek denekli araştırma yöntemlerinden çoklu yoklama modeline uygun olacak şekilde yürütülmüştür. Araştırmanın çalışma grubu, Erzurum ili İspir ilçesindeki bir ilkokulda öğrenim gören ve okuma güçlüğü yaşayan 2. sınıfa devam eden 3 (üç) ve 3. sınıfa devam eden 2 (iki) öğrenci olmak üzere toplam 5 (beş) öğrenciden oluşmaktadır. Katılımcıların zihinsel, görsel ve işitsel herhangi bir sağlık sorunu olmaması ayrıca akıcı okuma ve okuduğunu anlama düzeylerinin endişe düzeyinde olması araştırma için ölçüt olarak belirlenmiştir. Araştırma sürecinde okuma güçlüğü yaşayan öğrencilerin akıcı okuma ve okuduğunu anlama düzeylerini belirlemek için öğrencilere ön, ara ve son değerlendirme yapılmıştır. Katılımcıların akıcı okuma ve okuduğunu anlama düzeylerini belirlemede Yanlış Analiz Envanteri ve okuduğunu anlama soruları kullanılmıştır. Ön değerlendirme verilerine göre 5 (beş) öğrencinin de akıcı okuma düzeylerinin % 90 ve altında; okuduğunu anlama düzeylerinin de %50 ve altında olduğu belirlenmiştir. Bu veriler doğrultusunda öğrencilerin akıcı okuma ve okuduğunu anlama düzeylerinin endişe düzeyinde olduğu tespit edilmiştir. Uygulama 60 saat sürmüştür. Uygulamanın ilk yarısından sonra yani 30 saatlik bir uygulamadan sonra da ara değerlendirme yapılmıştır. Ara değerlendirme verilerine göre katılımcıların akıcı okuma ve okuduğunu anlama düzeylerinde gelişim olmasına rağmen 4 (dört) öğrencinin akıcı okuma düzeylerinin endişe düzeyinde; 1 (bir) öğrencinin de akıcı okuma düzeyinin öğretim düzeyinde olduğu tespit edilmiştir. Ara değerlendirme verilerine göre katılımcıların okuduğunu anlama düzeylerinde gelişme olmasına rağmen okuduğunu anlama düzeylerinin hala endişe düzeyinde olduğu tespit edilmiştir. 60 saatlik uygulamanın ardından yapılan son değerlendirme verilerine göre ise 5 (beş) öğrencinin de akıcı okuma ve okuduğunu anlama düzeylerinin öğretim düzeyine yükseldiği tespit edilmiştir. Uygulamanın ön değerlendirme ve son değerlendirme verileri doğrultusunda istatiksel açıdan anlamlı bir farklılık meydana getirip getirmediğini tespit etmek amacıyla SPSS Paket Programı'nda yer alan Wilcoxon İşaretli- Sıralar Testi ile analiz edilmiştir. Analiz sonuçları incelendiğinde uygulama ile katılımcıların akıcı okuma ve okuduğunu anlama düzeylerinde önemli bir oranda gelişme olduğu ve bu gelişmenin de istatiksel açıdan anlamlı bir farklılık meydana getirdiği tespit edilmiştir. Araştırma sonuçları eko (yankılayıcı) ve tekrarlı okuma stratejilerini şiir türü metinler üzerinden uygulamanın okuma güçlüğünü giderdiğini, akıcı okuma ve okuduğunu anlama becerilerini olumlu yönde etkilediğini göstermektedir.