SEARCH RESULT

Although many parameters for metallic alloy systems can be obtained in the literature, there are limited studies about the relationship between residual stress and tribological performance of the metallic alloy systems. In this study residual stress measurement was performed by straingauge method to investigate on residual stress, hardness and wear behaviours of Al-Cu-Ni Heusler Alloys before and after aging process. Wear tests were carried out using two different loads (10N and 20N) in dry sliding conditions. Results show that aging time effects mechanical behaviour of heusler alloys. Also Best wear resistance is belonging to the aged samples under load of 10N.

International Iron & Steel Symposium
UDCS

Fazil Hüsem Fatma MEYDANERİ TEZEL

Although many parameters for metallic alloy systems can be obtained in the literature, there are limited studies about the relationship between residual stress and tribological performance of the metallic alloy systems. In this study residual stress measurement was performed by straingauge method to investigate on residual stress, hardness and wear behaviours of Al-Cu-Ni Heusler Alloys before and after aging process. Wear tests were carried out using two different loads (10N and 20N) in dry sliding conditions. Results show that aging time effects mechanical behaviour of heusler alloys. Also Best wear resistance is belonging to the aged samples under load of 10N.

International Iron & Steel Symposium
UDCS

Fazil Hüsem Fatma MEYDANERİ TEZEL

Although many parameters for metallic alloy systems can be obtained in the literature, there are limited studies about the relationship between residual stress and tribological performance of the metallic alloy systems. In this study residual stress measurement was performed by straingauge method to investigate on residual stress, hardness and wear behaviours of Al-Cu-Ni Heusler Alloys before and after aging process. Wear tests were carried out using two different loads (10N and 20N) in dry sliding conditions. Results show that aging time effects mechanical behaviour of heusler alloys. Also Best wear resistance is belonging to the aged samples under load of 10N.

International Iron & Steel Symposium
UDCS

Fazil Hüsem Fatma MEYDANERİ TEZEL

These ores are primarily enriched in order to make low-grade iron ores (> 50% Fe content) available at the blast furnace, which can be fed directly to the blast furnace. The most widely used method of agglomeration after enrichment is pelleting. In this study, the characteristic features of three different pellet types, one domestic and two imported (Ferroexpo and east); chemical, physical and metallurgical properties have been determined. The element and compound analysis were performed with XRF and XRD devices. By using different size of sieves, grain size analysis and moisture were determined before entering the blast furnace. By the Rul (R40) test at 1050 °C, with the mix gas (%40 CO+ 2% H2 + 58% N2), the reduction rate of the furnace was measured by difference in height and pressure inside the furnace. The volume increase during reduction was determined by swelling test on 18 pellets at 900 C. The degredation index of the iron ores reduced by mix gas at 500 °C was determined by the LTD test. The crumbling and dusting indexies of pellets during transport in the plant was measured by the drum test. At the end of the research, it was found out that 3 different pellets provided by KARDEMİR A.Ş. were advantageous, and the changes in mineral ratios changed the technological test results and this effect on the blast furnace reactions.

International Iron & Steel Symposium
UDCS

Fatma MEYDANERİ TEZEL Neslihan ATALAY

Al based Sb - 42.4% Mg - 57.6% Al ternary eutectic alloy was melted by vacuum melting furnace, and was casted into kokil mould. Then, in order to observe the effect of heat treatment, samples were investigated as-cast and under heat-treated conditions. Designed samples were homogenized at 573 K for 1.5 h. The values of enthalpy of fusion (H) and the specific heat capacity (Cp) of the solid phase for Al based the ternary eutectic alloy were measured with DSC. The crystal structure parameters and the grain sizes for the alloys were investigated by XRD diffraction. Mechanical properties of the ternary eutectic alloy were studied with compression test. The effects of heat treatment on the microstructures and the microscopic fracture surface morphology of the aged samples were examined by FESEM. The microhardness for the alloys was measured from 5 different points with Vickers microhardness device. The compositions of the ternary alloys were determined by Energy Dispersive X-Ray (EDX) analysis.

International Iron & Steel Symposium
UDCS

Fatma MEYDANERİ TEZEL Yunus GENCTURK Ugur VELİ Mustafa Mert KULAK Orcun OLCAY Eren UZUN

In this study, effects of heat treatment on microstructure and structural properties of NiTi alloy were investigated. In this sence, the depence of shape memory behavior of NiTi alloy was examined by changes of heat treatment temperature and cooling conditions. Two group of specimens were used. One group was deformed by 50% and the other group was deformed 75%. Heat treatment temperatures were chosen 5000C and 600 0C. All specimens were cooled both in air and water to investigate the influence of cooling conditions. Microstructures were examined using Scanning Electron Microscope (SEM). Also DSC and XRD analysis were carried out for thermal and structural characterization.

International Iron & Steel Symposium
UDCS

Yuksel Akinay Fatma MEYDANERİ TEZEL Yasin Akgül

In this project, Al alloys with Al-10Sn-xSi (x = 2, 4, 6) composition will be melted in the graphite furnace by using a vacuum melting furnace, and melt coke molds will be poured to obtain tensile specimens. A portion of the specimen will then be annealed at 400 °C for 1.5 hours in the annealing furnace. For both non- tempering the samples annealed, step sanding, 6, 3, 1-micron particle size diamond suspension and felt the fine polishing, and finally, etching ending sample Material research development from SEM images, EDX analysis will be done. With SEM, surface morphology, composition analysis with EDX, diffraction pattern and crystallographic orientations and crystal parameters, phases formed and distribution of these phases, grain sizes will be examined and their structural properties will be revealed as a result.

International Symposium on Light Alloys and Composite Materials
UHAKS

Fazil Hüsem Salih Bektaş Fatma MEYDANERİ TEZEL

Abstract Aluminium is widely used in aircraft and automotive industry. Since aluminium and its alloys have many excellent properties such as low density, good corrosion resistance, machinability and electrical conductivity compared to other materials, high-performance materials, which are both very durable and lightweight, must be used in the manufacture of air and space vehicles. These loads are subjected to thermal shocks with sudden temperature changes in power systems, corrosion due to ambient conditions, and resultant fatigue of different loads encountered in working conditions. The formation and progress of fatigue cracks is one of the most important issues in aircraft design. For example, it has been observed that multiple fractures resulting from the formation and progression of multiple fatigue cracks have resulted in considerable damage.

International Symposium on Light Alloys and Composite Materials
UHAKS

Fazil Hüsem Fatma MEYDANERİ TEZEL Serdal HAN Hayrettin Ahlatçı Atakan BOĞA Melih SEMERCİ

With the development of technology, light engineering alloys have recently become a popular group of material. The most important consideration in the development of these alloys is production cost, applicability in technology, temperature and composition. For this reason, in this study, the effects on corrosion resistance of composition and annealing parameters in light Al-based Al-Mg-Sb eutectic alloy systems with commercial and industrial design were investigated depending on precipitation and intermetallic phase distribution Al based Mg-Al-Sb eutectic alloys were melted by induction furnace and were casted into kokil mould. Then, samples were annealed at 573 K with vacuum furnace. Cyclic Potentiostatic test was applied with the PARSTAT 4000 device for corrosion rate. In the experiment, firstly, the change in corrosion potentials between the working electrode and the reference electrode since the dipped reference electrode and working electrode into the 3.5% NaCI solution was measured as mV versus time without passing current on the system. After reaching the equilibrium potential (Ekor), potentiodynamic polarization curves were recorded from the cathodic to anodic direction. Measurements were carried out at open circuit potential (15 min), and the graphs of the change of the potential versus the current density were obtained, and the corrosion rates were determined for the heat treatment and heat-free samples.

International Symposium on Light Alloys and Composite Materials
UHAKS

Fatma MEYDANERİ TEZEL Ozan Akyol Berkay Aras Çağla Elçin YAĞCIOĞLU

Aluminum is one of the most commonly found elements in nature and the most commonly used metal after engineering steel. Recently, aluminum and its alloys are an important material for engineers and designers in industry due to their low strength, good thermal and electrical conductivity, increased strength properties and corrosion resistance. Since aluminum and its alloys have many excellent properties such as low density, good corrosion resistance, machinability and electrical conductivity compared to other materials, it is widely used in aircraft and automotive industry. The aircraft and the automotive industry need to use light metals with high strength. High-performance materials, both very durable and lightweight, must be used in the manufacture of air and space vehicles. These loads are subjected to thermal shocks with sudden temperature changes in the power system, corrosion with the effect of ambient conditions, consequent fatigue of different loads encountered in working conditions of these materials. The formation and progress of fatigue cracks is one of the most important issues in aircraft design. Aluminum alloys are economical in many applications. It is used in the automotive industry, in the aviation industry, in the making of machines and devices, as cooking vessels, in the bodies of electronic devices, pressure vessels, cryogenic applications and other fields. Therefore, in this study, the corrosion behaviors of Al-Sn-Zn alloys were determined by applying the mass loss corrosion test. The mass loss-time graph obtained is given in Figure 1 According to the test results, the sample with 70% Sn content undergoes less corrosion over time, while the samples containing Zn and Al undergo more corrosion over time.

International Symposium on Light Alloys and Composite Materials
UHAKS

Fatma MEYDANERİ TEZEL Serdal HAN Çağla Elçin YAĞCIOĞLU

Sn-Zn based alloys are an alloy group of particular interest as lead-free solder in the electronics industry. Considering the characteristics of solder alloys, they are producible, their reliability and environmental suitability are remarkable; such as melting temperatures, solder ability, flow ability, density, thermal and electrical properties, corrosion and oxidation behavior, surface tension, rework ability and cost. Lead-free solder alloys are also sensitive to environmental and human health and are among the main reasons for preferring these alloys. Sn-Zn solders have a variety of fascinating properties such as low melting temperature at 198 C. In addition, in the metal coating industry, Zn-Sn alloys are now used as protective coatings on ferrous base metals. Low cost Zn-Sn coatings show high corrosion resistance and are seen as promising candidates to replace toxic cadmium and allergenic nickel coatings [1-3]. In this study, it is aimed to form alloys by combining Sn and Zn elements by casting method. Microstructural properties of Sn-50 wt.% Zn and Sn-80 wt.%Zn alloys were examined with SEM, EDX, XRD devices. Average micro hardness values of Sn-[x] wt. % Zn [x=50 and 80] alloys were measured to be 62.1 ve 49.2 (Hv0.05). According to these results, micro hardness values only depend on the composition, and decrease with increasing of Zn composition. Mechanical properties (yield, elongation, elongation) were also obtained by using a tensile tester. The tensile test results for Sn- 50wt.% Zn and Sn-80wt.%Zn indicating that the sample with the best mechanical properties is Sn-50wt.% Zn. In addition, the tensile value obtained for the Sn-50wt.% Zn sample is 78.26 MPa, the unit strain is 5.8% and the yield stress is 53.76 MPa. Also, the corrosion behavior of Sn-50 wt.% Zn and Sn-80 wt.%Zn alloys was determined by applying the mass loss corrosion test. According to the corrosion tests, the corrosion curves were given in Fig. 2

International Symposium on Light Alloys and Composite Materials
UHAKS

Fazil Hüsem Fatma MEYDANERİ TEZEL Salih Bektaş

Pb and Pb-containing compounds are prohibited to use in European Union, because of damaging the environment and human health. Limitation of lead used in the industry for more appropriate development policies to protect the environment is emphasized by most countries. In this context, great efforts for the development of lead-free alternative alloys instead of Pb-Sn eutectic solder alloy is shown [1-2]. Both economically and in terms of other physical and chemical requirements of lead-free solder alloy is required to meet. Sn-Zn eutectic alloy of lead-free solder alloy as prominently provides electronic merge without any modification and is expected to be one of the best alternatives to maintain the existing production line [3-4]. In addition, both micromechanical and metallurgical properties in terms of controlling the microstructure, strength, a casting alloy is complex in terms of silence and ductility. Thermal variables and their impact on the microstructure morphology depending on the heat transfer solidification conditions are influenced by the temperature and composition and are affected all the features as a direct result [5-7]. In this study, Sn-1wt.% Zn, Sn-9wt.% Zn and Sn-14wt.% Zn alloys were cast into the kokil mold. Structural, surface and composition analyses of the obtained alloys were obtained by using SEM, EDX, XRD devices. The variation of Zn amount has a great impact on the grain size, and flake or needle shape distributions of Zn phase in Sn matrix result in different effects on hardness. Also, the microstructures changed from tetragonal solid solution phase to before monoclinic and orthorhombic solution phase and then hexagonal phase. Mechanical properties (yield, elongation, elongation and breakage) were also obtained by using a tensile tester. The tensile test results for Sn-1wt.% Zn, Sn-9wt.% Zn and Sn-14wt. indicating that the sample with the best mechanical properties is Sn-9wt.% Zn. In addition, the tensile value obtained for the Sn-9wt.% Zn sample is 105.8 MPa, the unit strain is 12.8% and the yield stress is 85.548 MPa. Average micro hardness values of Sn-[x] wt. % Zn [x=1, 9, 14] alloys were given Table 1 According to these results, micro hardness values only depend on the composition, and increase with increasing of Zn composition.

International Symposium on Light Alloys and Composite Materials
UHAKS

Fazil Hüsem Ceyda Albayrak Furkan Nergiz Fatma MEYDANERİ TEZEL Umur Can Hamutoğlu Salih Bektaş

In addition to the good mechanical and physical properties of the engineering materials used in today's industrial, the materials to be produced need to be more economical. Al-Sn-Si alloy has a composition which is accepted especially in the automotive industry due to its very good strength / lightness ratio, and it is preferred in engine, chassis support components and wheel rims for reducing the of the car weight, fuel economy, lower environmental emission values. However, the rapid changes in the automotive industry and the challenging competition ambiance push the manufacturers to meet customer demands, and they urge the manufacturing industry to appropriate methods in order to be able to respond to the demands with high quality. At this point, it is necessary to understand the characteristics of the materials of the produced components in a good way and to carry out studies to meet their needs. Therefore, in this study, the effects on corrosion resistance and friction-wear properties of composition and annealing parameters of Al-based Al-Sn-Si alloy systems have commercial and industrial design have been experimentally investigated. Al-based Al-10Sn-xSi (x = 2, 4, 6) alloys are melted in the graphite furnace by using a vacuum melting furnace, and melting sample are poured into mold to obtain compression test samples. Then, a portion of the specimen is annealed at 400 C for 1.5 hours in the annealing furnace. For both annealed and non-annealed samples, surface morphologies with SEM, compositional analysis with EDX, crystallographic orientations with XRD diffraction pattern and crystal parameters, formed phases and distribution of these phases, grain sizes were investigated after metallographic processes. Vickers micro hardness values and compression tests were then applied for heat treated and non-heat treated samples. Accordingly, it has been determined that the strength of the heat treated samples and the increased amount of the Si element is increased.

International Symposium on Light Alloys and Composite Materials
UHAKS

Salih BEKTAS Fazil Hüsem Fatma MEYDANERİ TEZEL

Abstract Aluminum, which is in the light metal category due to the development of technology and the technical features it possesses, is widely used in many fields of industry. In practice, the ratio of the strength to the weight (specific strength property) is very large; the soft and one-third the weight of steel. When alloying elements are added, the mechanical properties can be increased to be comparable to steel; this makes aluminum usable for medicine, construction, food, automotive and aerospace industries. All the hardening elements added to aluminum reduce thermal and electrical conductivity and elongation. The applied heat treatments change plasticize and hardness. The manganese has an effect of increasing the toughness and ductility properties, but it has become an essential element in the secondary additions by increasing the tensile strength without reducing the corrosion resistance. In this study, the mechanical properties of alloys with different compositions of Al-based Al-Mn alloys were determined by Vickers Hardness Tester, Tensile Test and the effect of heat treatment was discussed. Accordingly, the average hardness values of Al-x Mn (x = 0.1, 0.2, 0.3) alloys were measured as 47.7, 50.8 and 53.3 for the samples not subjected to heat treatment and 50.2, 54.1 and 81 for the samples subjected to heat treatment, respectively. According to the tensile test results, the order of Al-x Mn (x = 0.1, 0.2, 0.3) alloys is max. tensile strength 87.9, 97.4, 101.23 MPa, heat treated samples 101.15, 106.6, 125.4. SEM, EDX and XRD and microstructural and surface morphologies related to the composition were investigated.

International Symposium on Light Alloys and Composite Materials
UHAKS

Fazil Hüsem Fatma MEYDANERİ TEZEL Atakan BOĞA Serdal HAN Melih SEMERCİ