SEARCH RESULT

One of The main purpose of fracture mechanics is materials selection compatible with the fracture toughness. The higher stress at crack tip and lower zone of fracture area provides less dimensions and crack length of specimens. According to ASTM E 399, evaluated KIC, measured plane strain fracture toughness (KIC) related to parallel direction of crack propagation which is lower than cross sectional area, occurrence of pre-crack, selection of COD gauge, type of cracks, and drawbacks during the measurements are clarified.

International Iron & Steel Symposium
UDCS

Fazil Hüsem

Crack occurrence and its effect on materials are one of the crucial problems in defence, aircraft and railway industry. Related to the phenomena, the evaluation of the methods and analysis on the materials selection gains inmportance. In this study, ASTM E647 and BS ISO 12108 standards are investigated used in the calculation of FCGR ( fatigue crack growth rate).

International Iron & Steel Symposium
UDCS

Fazil Hüsem

—In this study, fatigue strength and microstructural changes of AISI 1040 steel with different heat treatment parameters were investigated. 1040 steel is a material used in many areas today. Some of the material application areas can be subjected to cyclical loads. Fatigue strength, such as abrasion and tensile strength, is also very important in these materials. AISI 1040 steel can be easily heat- treated to increase strength. The samples were incubated at 920 ° C for 4 hours and controlled cooling in air, oil, water and oven. The microstructures of the samples after heat treatment were examined by optical microscope. Vickers hardness was performed for all samples. Force controlled fatigue test was performed. Broken surface images of fractured specimens were taken on Nikon ShuttlePix device during the test. The hardness of the water cooled sample was better than other heat treatment samples. It was observed that the increase in fatigue strength as a result of the hardness and pulling points increased.

International Iron & Steel Symposium
UDCS

Salih Bektaş Fazil Hüsem

In this study, head hardening process was applied for R260 quality rails. Microstructures of rails were carried out using Scanning Electron Microscope (SEM). Hardness distribution of head parts were also evaluated for two category samples (heat treatment and non heat treatment). Wear tests were performed under three different loads (10N, 20N and 40N) in both %3.5NaCI solution and dry conditions. Worn surfaces were characterized by Nikon Shuttlepix, Profile projector and SEM. Results clearly show that, head hardened rails exhibited better wear performance especially under load of 10N in dry conditions.

International Iron & Steel Symposium
UDCS

M. Emre TURAN Fazil Hüsem Yasin Akgül Yavuz Sun Hayrettin Ahlatçı

In this study, effect of boron nitride particles on the mechanical properties of aluminum composites reinforced with BN particles was investigated. Experimental procedure was started with mixturing of powders in the turbula mixer. Hot press was applied at 550 C in argon atmosphere. For characterization of microstructure, scanning electron microscope (SEM) analysis was done. Compression test was applied for determination of strength. Vickers hardness was used to measure hardness of samples.

International Iron & Steel Symposium
UDCS

Yasin Akgül Yuksel Akinay Fazil Hüsem Hamza Simsir Safa POLAT

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

This study aims to investigate fatigue crack growth and fracture toughness behavior in grooved rails. R260 grade and R260 grooved grade rails were used for analysis to understand effect of rail geometry on fracture properties of specimens. Fracture surfaces and microstructures of specimens were examined by the use of Scanning Electron Microscope(SEM) and Nikon Shuttlepix Digital Microscope. Results show that, fracture toughness and fatigue crack growth behavior are effected by the geometry of specimens due to plastic deformation mechanism on head parts.

International Iron & Steel Symposium
UDCS

Fazil Hüsem M. Emre TURAN Hayrettin Ahlatçı

Damascus steels are produced by traditional methods and mostly used in the construction of decorative tools. This study aims to investigate wear and mechanical behaviors of damuscus steels which are exposed different forging type. Wear tests were applied for two different category of samples under the loads of 30N and 40N. In addition to wear tests, tensile test was carried out to understand the influence of forging type on mechanical behavior in this quality steel. Results show that, wear performances are changed with forging process and best wear resistance could be seen under loads of 30N for all samples.

International Iron & Steel Symposium
UDCS

Eren SALIS Umit YAVUZ Nurdan KUCUK Fazil Hüsem Hayrettin Ahlatçı Memis ISIK Pınar UYAN

This study aims to determine residual stress distribution in head, web and foot parts of two different quality grooved rails and also to understand effect of carbon content on residual stress in rails. Strain gauges were glued on three regions of specimens and cutting method was applied for residual stress measurement according to the TS EN 13674-1 railway rail standard. Scanning Electron Microscope (SEM) and Optic Microscope (OM) were used for microstructure analysis of regions where the residual stress measurements were performed. Results show that, compressive residual stress is an effective stress type compared to the R260 grade rails. However, R260 grade grooved rails have higher residual stress value than R220 grade grooved rails especially in head parts of specimens.

International Iron & Steel Symposium
UDCS

M. Emre TURAN Yavuz Sun Fazil Hüsem

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

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

In this work, Brinell hardness test, impact test, bend test results of four different types of honeycomb composite materials, which are important for todays in the Civil Aviation Sector and which have been undergoing significant improvements over the past 20 years, have been investigated. The thickness of the mechanical properties of the composites differed with the length of the part and the chemical resin used. The white material in 1,2 cm thickness is used in side and ceiling in cargo area. The light yellow materials is 1,2 cm thickness and is used on the cargo floor and on the wet and dry floors of Airbus, Boeing branded aircraft. Black materials (on wet floors) material in 9,9 cm thickness and used in Passenger Glasses. Yellow Color resinized honeycomb composite in lyophilized form is 1cm thick and used on the bottom of cargo section. Hardness measurements were carried out with a 2.5 mm ball and a load of 187.5 kg under the Brinell Hardness Tester . When the hardness results were examined, when the white composite was damaged, the highest hardness value was found as yellow composite (54,92 HB) value of black composite (26.02 HB). The open saddle stiffness is 31,43 HB.

International Conference of Advanced Materials and Manufacturing Technologies
ICAMT

Muharrem Ilbeyi Incedere Emre Yildirim Emre Demirci Batuhan Ozusta Hayrettin AHLATCI Yavuz Sun Yunus Türen SAİT ÖZÇELİK Fazil Hüsem