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Öğe An application of finite element method in material selection for dental implant crowns(Walter De Gruyter Gmbh, 2021) Sensoy, Abdullah T.; Colak, Murat; Kaymaz, Irfan; Findik, FehimMaterials used for dental crowns show a wide range of variety, and a dentist's choice can depend on several factors such as patient desires, esthetics, tooth factors, etc. One of the most important issues for implant surgery is the primary stability and it should be provided to minimize the risks of screw loosening, failed osseointegration, or nonunion. The current study aims to present the Finite Element Analysis (FEA)-based material selection strategy for a dental crown in terms of reducing the aforementioned risks of dental implants. A virtual surgery mandible model obtained using MIMICS software was transferred to the ANSYS and material candidates determined using CES software were compared using FEA. The results indicated that ZrO2+Y2O3 (zirconia) has shown a 12.79% worse performance compared to Au83-88/Pt4-12/Pd4.5-6 alloy in terms of abutment loosening. On the other hand, zirconia is the most promising material for dental crowns in terms of the stability of the bone-implant complex. Therefore, it may show the best overall performance for clinical use. Moreover, as suggested in this study, a better outcome and more accurate predictions can be achieved using a patient-specific FEA approach for the material selection process.Öğe Characterisation of aluminum alloys by octopus fluidity test(Gazi Univ, 2024) Erzi, Eray; Yuksel, Caglar; Gursoy, Ozen; Colak, Murat; Dispinar, DeryaAim Determination of fluidity and tensile property characteristics of A206, A201 and A380 alloy with new octopus design Design & Methodology Melting and casting of alloys into sand moulds. Measurement of fluidity length and tensile properties Originality New fluidity test mould design where different cross section thicknesses are used to characterise the alloy properties Findings A356 has the lowest fluidity. A201 has lower fluidity compare to A206 but has the highest strength. A380 has similar characteristics with A201 Conclusion A380 can be an alternative choise for A201 alloy Declaration of Ethical Standards The authors of this article declare that the materials and methods used in this study do not require ethical committee permission and/or legal-special permission.Öğe Characterization of properties of Vanadium, Boron and Strontium addition on HPDC of A360 alloy(Elsevier Science Sa, 2021) Gursoy, Ozen; Colak, Murat; Tur, Kazim; Dispinar, DeryaThe demand for lighter weight decreased thickness and higher strength has become the focal point in the automotive industry. In order to meet such requirements, the addition of several alloying elements has been started to be investigated. In this work, the additions of V, B, and Sr on feedability and tensile properties of A360 has been studied. A mold design that consisted of test bars has been produced. Initially, a simulation was carried out to optimize the runners, filling, and solidification parameters. Following the tests, it was found that V addition revealed the highest UTS but low elongation at fracture, while B addition exhibited visa verse. On the other hand, impact energy was higher with B additions.Öğe Determination of Acceptable Quality Limit for Casting of A356 Aluminium Alloy: Supplier's Quality Index (SQI)(Mdpi, 2019) Erzi, Eray; Gursoy, Ozen; Yuksel, Caglar; Colak, Murat; Dispinar, DeryaAluminium and its alloys have been widely used in the automotive industry for some time and A356 is one of the most popular aluminium alloys today in the sector. It contains approximately 7 wt.% Si and 0.3 wt.% Mg. Due to the defects that may be present in the cast parts, expected mechanical properties may not be reached and this alloy may perform in service under its potential. In a low pressure die casting, several precautions have to be taken in order to produce high quality and defect-free castings. Temperature of casting and the schemical composition of the melt is recorded continuously. Die temperature, pressure levels and their durations are optimized; degassing and fluxing operations are performed. Yet, regardless of the precautions, there could still be rejected parts. It is becoming clear that a good quality raw material is one of the most underrated points of the industry and that the starting material has a great effect on the final product and it should be taken in to account more seriously. Therefore, regarding the first rule of Campbell's 10 Rules of Casting, in this study, the quality of the starting material of supply chains for a wheel manufacturer was investigated. Chemical compositions were compared, fluidity tests, mechanical tests and bifilm indexes of these various sources and ingots were measured and a final quality index was proposed to create a reference for the quantification of quality of supplier's ingots. This new index was compared with the rejection rates.Öğe The effect of cooling plate, mechanical vibration, and grain refinement on the microstructure and hardness of A380 produced by sand mold(Taylor & Francis Ltd, 2024) Uslu, Emin; Tigli, Ahmet; Colak, MuratThe mechanical properties of aluminium alloys can be increased by controlling the grain size and morphology of the alloy. In these studies, mechanical vibration, cooling slope plate (CSP), and grain refiner were applied on sand mould casting using A380 alloys. The hardness, and microstructure of the cast samples are investigated. These processes lead to the refinement of grain structures and a decrease in the tendency for dendritic structure formation. The Effect of the solidification time (modulus) on the microstructure is investigated. It was determined that the solidification time varies depending on the section thickness, which affects the SDAS values. It was observed that the lowest SDAS values were in CSP and the highest values were in grain refiners added casting. The lowest hardness value was recorded at CSP casting. Meanwhile, the grain refiner added vibration casting exhibits the highest hardness.Öğe Effect of Erbium Addition to A380 Aluminum Alloy on Mechanical and Microstructural Properties(Springer, 2026) Gultekin, Cagri; Colak, Murat; Tabak, Yasemin; Sensoy, Abdullah TahirThere are many studies on improving the properties of aluminum alloys, but the addition of rare earth elements occupies a particularly important place among them. In this study, the effect of erbium (Er) addition on the microstructure and mechanical properties of A380 aluminum casting alloy was systematically investigated. A series of alloys with varying Er contents (0.03%, 0.05% and 0.1 wt.%) was fabricated using the conventional casting method. The addition of Er led to significant grain refinement, primarily due to the formation of Al3Er intermetallic particles, which acted as potent nucleation sites during solidification. Optical microscopy and SEM analyses confirmed the morphological transformation of the eutectic silicon phase into a finer and more fibrous structure. Mechanical testing revealed that the alloy containing 0.1 wt.% Er exhibited the highest ultimate tensile strength (236 MPa), elongation (4.56%), and hardness (87.6 HB), indicating an optimal balance between strength and ductility. The improvement is attributed to both microstructural refinement and dispersion strengthening mechanisms. These results suggest that controlled Er addition can be an effective strategy for enhancing the performance of cast Al-Si alloys, making them promising candidates for demanding structural applications in the automotive and aerospace industries.Öğe EFFECT OF SCRAP RATIO ON LIQUID METAL QUALITY OF LOW-PRESSURE DIE-CASTING (LPDC) ALLOY USING ROTARY DEGASSING(Konya Teknik Univ, 2025) Tokatli, Mehmet; Colak, Murat; Yuksel, CaglarAlthough various processes are used in aluminum liquid metal cleaning, environmentally friendly, economical and applicable methods should be preferred in industry. Among these methods, the Density Index test based on the reduced pressure test (RPT), which is widely used to measure the efficiency of the rotary degassing process, and the K-mold test method, which offers fast and practical results were carried out. The effects of rotary degassing method on the liquid metal quality of AlSi7Mg0.3 (A356) aluminum alloy charges prepared with different proportions of scrap and ingots were evaluated using a constant 5l/min gas flow rate, a constant 5 min process time and a constant 300 rpm rotor rotation speed. The results show that the Density Index values can be reduced from 1.48% to around 0.74% with increasing scrap rate, while K-mold values can be reduced from 2.8 to 0.6. It was also shown that the rotary degassing method is effective in liquid metal cleaning, and the K-mold test can be used as a very practical control tool for evaluating liquid metal quality.Öğe Evaluation of Fe Content on the Fluidity of A356 Aluminum Alloy by New Fluidity Index(Springer Int Publ Ag, 2024) Durmus, Melek; Dispinar, Derya; Gavgali, Mehmet; Uslu, Emin; Colak, MuratElements 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 degrees C and 750 degrees 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.Öğe Exploring alternative polymer materials for joint liners: a software-guided material selection(Iop Publishing Ltd, 2024) Yilmaz, Galip; Gerdan, Zeynep; Colak, MuratThis study explores the alternative polymer materials and selection process for joint implant liners, focusing on applying CES Selector software to identify suitable polymer materials. CES Selector provides an easy-to-use interface. It offers multiple selection methods, including boundary values and property constraints. Seven materials were excluded from the analysis, resulting in 19 potential candidates, including unconventional options like EVOH, PCTA, PESU, PI, PPA, PPC, PPSU, and PSU. The materials underwent evaluation based on key criteria, including tensile strength, Young's modulus, compressive strength, fatigue strength, and fracture toughness. Overall, TPU exhibited a remarkable combination of high mechanical strength and adaptable Young's modulus, making it a top contender. However, in other evaluation criteria, PI surpassed TPU, solidifying its potential as a superior choice. This systematic approach provides valuable insights for engineers and designers seeking innovative materials for joint implant liners. The study results broaden the range of materials used in implant manufacturing, providing potential alternatives that offer better long-term durability and performance.Öğe Importance of Melt Cleaning Parameters on Reliability of Tensile Properties in A356 Alloy(Springer Int Publ Ag, 2025) Tigli, Ahmet; Uslu, Emin; Colak, Murat; Dispinar, DeryaThis study examines how melt treatment and pouring temperature affect the microstructure and mechanical properties of A356 aluminum alloy. Samples were cast under degassed, non-degassed, and upgassed conditions at 725, 750, and 775 degrees C. Melt quality was assessed using the reduced pressure test (RPT) and the bifilm index (BI), while microstructural features were analyzed via SEM and EDS. Tensile testing and Weibull statistics were used to evaluate mechanical performance and variability. Results showed that by improper degassing the reproducibility of mechanical properties decreased regardless of hydrogen content of the melt. When bifilm index (BI) was high (> 50 mm), the ductility was lowered and caused greater variability in strength and elongation. SEM confirmed large oxide films in samples, linked to the brittle fracture. The work also highlighted the importance of melt cleaning parameters for the reliability of cast aluminum alloys regardless of the hydrogen content.Öğe The influence of metallostatic pressure, grain refiner, and modification on the critical solid fraction (CSF) of cast A380 alloy(Academic Publication Council, 2021) Colak, Murat; Dispinar, DeryaIn this work, porosity formation with regard to the change in the metallostatic pressure was investigated. Different geometry was generated to simulate the effect of pressure on critical solid fraction. A380 alloy was sand cast. Additionally, the effect of grain refiner and modifiers was also investigated. Samples were subjected to X-ray radiography and density measurement to quantify the pore size and distribution.Öğe Investigating the Optimum Model Parameters for Casting Process of A356 Alloy: A Cross-validation Using Response Surface Method and Particle Swarm Optimization(Springer Heidelberg, 2020) Sensoy, Abdullah Tahir; Colak, Murat; Kaymaz, Irfan; Dispinar, DeryaThis 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 degrees C), casting temperature (680-760 degrees 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 highestR(2)(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 degrees C, 760 degrees 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.Öğe Investigation of the Effect of Inoculant and Casting Temperature on Fluidity Properties in the Production of Spheroidal Graphite Cast Iron(Springer India, 2021) Colak, Murat; Kaya, SinanWorking 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.Öğe Investigation of The Effect of Molding Material Difference on Design in GGG70 Ductile Cast Iron Production(2024) Şekerden, Mete; Keskin, Muhammet Emin; Durmuş, Melek; Colak, MuratThe casting process involves filling a prepared mould cavity with molten metal, which takes the shape of the container. While the liquid metal takes the shape of the container it is in, the method is attractive, while the volumetric changes during the liquid-solid transformation reveal the importance of moulding design for the manufacture of solid parts. Especially in cast irons, moulds with the same design may produce different results depending on the changing casting and foundry conditions because the volumetric change that occurs during the solidification of ductile cast irons is affected by many parameters and develops differently than in steel and aluminium castings. This study used model wet and resin molding materials to create single and double-riser moulding and castings with different section thicknesses. The importance of the type of mold material used in castings and the number of feeders for the robust production of the cast part was evaluated using experimental and modeling techniques. When the results were examined, it was seen that the shrinkage risk was lower with resin mould than with green sand moulding. In addition, depending on the riser connection point, the importance of the riser neck has emerged.Öğe Investigation of the Effect of Niobium Addition on Fluidity and Mechanical Properties in Casting of Aluminum Alloys(Springer Int Publ Ag, 2026) Colak, Murat; Yalcin, OnderAluminum 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.Öğe Investigation of the effect of solidification time and Nb addition on the microstructure of A356 aluminum alloy castings(Gumushane University, 2024) Yalçin, Önder; Tokatli, M.; Tigli, Ahmet; Colak, MuratAluminum alloys are very important engineering materials due to their lightness, corrosion resistance, high electrical and thermal conductivity, high strength, and ductility. Therefore; It is widely used in many areas such as automotive, aviation, defense, space industry, machinery manufacturing, and food industry. The demand for high-quality aluminum products is also growing as their applications increase. This study aims to explore the influence of adding 0.03%, 0.06%, and 0.1% niobium to the A356 aluminum casting alloy on the resulting microstructure. The investigation focused on permanent step mold casting with different cross-sectional profiles. In the study, melting, liquid metal cleaning (lance degassing), permanent mold casting, metallographic sample preparation, microstructure examination, and image analysis techniques were used. It was observed that SDAS and SDAL of A356 increased with decreasing cooling rate. With the addition of 0.1% Nb, the dimensions of SDAS demonstrated a reduction when contrasted with the as-received A356 castings. © 2024, Gumushane University. All rights reserved.Öğe Investigation of the effect of the addition of grain refiner and modifier addition on wear properties in sand and permanent mould casting of A357 and A380 aluminium alloys(Taylor & Francis Ltd, 2022) Colak, Murat; Arslan, IbrahimThe aim of this study is to improve the tribological behaviour of aluminium alloys by using grain refiner and modifier. The effects of Al5Ti1B grain refiner and Al10Sr modifier additives on friction and wear properties on A380, A357 alloys produced by pouring sand andpermanent mould casting were investigated. Abrasion tests were carried out under dry conditions against St1040 steel disc using a pin-disk system with 20 N load and 1.0 m/s sliding speed. It was determined that grain refiner and modifier additives decrease the friction coefficient and increase the wear resistance. It was determined that the samples produced by permanent mould casting method decreased the friction resistance by 9% and the abrasion resistance increased by 40% compared to the samples produced in sand mould. The lowest wear rate was obtained in A380 alloy with TiB and Sr added with a value of 4.87 x 10(-11) m(2)/N.Öğe Investigation of the Effect of Vanadium Addition on Mechanical Properties in A356 Aluminum Casting Alloys(Springer Int Publ Ag, 2025) Ceker, Merve; Colak, MuratThe superior properties of aluminum alloys are further improved by the addition of different elements and gain new qualities. In the aluminum casting industry, vanadium (V) addition plays an important role to improve the mechanical and physical properties of these alloys. In this study, different amounts of V (0.03%, 0.06% and 0.1%) were added to A356 alloy, and its effects on mechanical properties and microstructure were investigated experimentally. The liquid metal degassing process was applied in all experiments in order not to affect the results of gases and inclusions in the liquid metal before casting. In the study, degassing was assessed by the Reduced Pressure Test (RPT). Tensile and hardness test specimens were performed with specimens obtained from mechanical test molds. When the results were examined, the elongation amount, which was 2.7% in A356 casting without addition, increased with the addition of V and reached a maximum value of 7.6% with 0.1% V addition. Tensile stress values were 137 MPa in A356 castings without addition, 159 MPa with 0.03% V addition, 168 MPa with 0.06% V addition and increased up to 185 MPa with 0.1% V addition.Öğe Investigation of the Effects of Filling Speed, Casting Temperature and Metallurgical Quality on Fluidity of Lamellar Graphite Cast Iron at Different Section Thicknesses(Springer Int Publ Ag, 2024) Kose, Sami; Sukuroglu, Ebru Emine; Colak, MuratIn 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.Öğe Low-velocity impact analysis of metal-composite joints with grain-refined A356 and reinforced epoxy adhesive using six node pentahedron cohesive elements(Taylor & Francis Ltd, 2026) Erbayrak, Engin; Colak, Murat; Noberi, CansuThis study evaluates the strength of double lap joints composed of metal composite adherends and epoxy adhesive subjected to low impact energies (20 J, 40 J). The study was carried out through experimental and numerical methods to understand the strength of lap joints comprehensively. In the production of double lap joints, A356 aluminum and grain-refined aluminum adherends were used as the metal components. To refine the grain structure, titanium (Ti) and boron (B) were added to the liquid metal at a rate of 0.01% of the total metal weight (A356-TiB). The composite laminates consisted of glass/epoxy and aramid/epoxy, made with unidirectionally oriented fibers. Araldite 2015 epoxy adhesive, available in both unreinforced and copolyester-reinforced forms, was utilized to bond the metal and composite materials. In the numerical analysis of double-lap joints, the metal and composite adherends are modeled using 8-node solid elements, while the adhesive is represented by 6-node pentahedron cohesive elements. Furthermore, a surface-to-surface, two-way treatment of contact was created between the impactor and the metal adherend. Consequently, the maximum impact loads obtained from the numerical analysis are in good agreement with the experimental results for both impact energies.
