Ahmet Atak | Gazi University (original) (raw)

Papers by Ahmet Atak

Universal Journal of Mechanical Engineering, 2019

Design affects the entire lifespan of a product. Humans design ideas in their environments, espec... more Design affects the entire lifespan of a product. Humans design ideas in their environments, especially to meet their own needs. People come to design ideas and abilities from various objects and events in nature, and use these to increase their design capabilities. With the increase in human population, proliferation of product needs, and the dangerous use of products, the ethical risks have increased. The risks within unethical designs have now reached all levels of human life. Products have been introduced to the market without considering their ethics, and in many of them, only the material purpose has been pursued, instead of the benefit to humanity. This research focused on the goal of the product designers, which is to design and develop a product, while contributing to the awareness that the product needs to be subjected to both risk and ethical analyses as with all other requirements. The dominant task of this study is to enable designers and their designs to develop their own ethical discourse and concepts. In doing so, the most forward aim is to not damage humans, but to design what is useful. The impact on the designer is to have ethical responsibility for their designs.

Aluminium Alloys - Design and Development of Innovative Alloys, Manufacturing Processes and Applications [Working Title]

Installation and repair of hydraulic installations are carried out by joining the pipes in the fi... more Installation and repair of hydraulic installations are carried out by joining the pipes in the field. Pipe connections in aviation are made in a very narrow space and field. For this reason, fitting swaging method is used to connect the fittings to the pipes with a hydraulic hand tool. The basis for developing a swaging tool is knowledge of the design parameters for the plastic deformation of the swaging circle fitting. In addition to the design parameter, pipes have to be joined in cryogenic vacuum conditions, which require sealing in such sensitive and harsh conditions. In this study, the effect of swaged circle fitting designs on tightness and strength was determined and different swaging methods were examined for its improvement. Different geometric swaged circle fittings are designed and analytical and numerical models are solved. The solution results obtained show the characteristic effect of the fitting swaging analysis methodology and the swaged circle fitting design on the ...

Universal Journal of Mechanical Engineering

The strength, failure location and modes of AZ31B Magnesium sheets with 1.5 mm thickness, joined ... more The strength, failure location and modes of AZ31B Magnesium sheets with 1.5 mm thickness, joined using friction stir spot welding (FSSW), can be determined using tension-shear tests. However, the joined materials have different tension test and elastic-plastic characteristics. Elastic analysis methods for spot welding have been examined in detail in literature. However, if the material has narrow elastic and large plastic area characteristics, such as AZ31B, elastic-elastic analysis methods are deficient. The development and application of elastic-plastic analysis methods are required for such soft metal materials. In this study, the elastic-elastic and elastic-plastic analytical stress mechanisms were investigated. Strain and force equations were then derived using an analytical approach. These developed equations were based on the FSSW-Tension-Shear-Test and verified using Finite Element Method (FEM)-Analysis and tension-shear tests. In addition, the location of failure was also determined. It is possible to predict failures without performing tension-shear tests using the proposed analytical equations.

Civil Engineering Journal

In various fields of engineering, the assembly and repair of hydraulic installations are accompli... more In various fields of engineering, the assembly and repair of hydraulic installations are accomplished by joining the pipes. In such applications, the ring swaging method is used to connect the fittings to the pipes by means of a hydraulic hand tool. The basis to develop a swaging tool relies on the knowledge of the design parameter that influence plastic deformation of the swaging ring. In addition to build control over the design parameters, it is necessary to join pipes under severe conditions such as cryogenic vacuum and constrained space which require an intact sealing. In this study, the effect of swaging ring designs on sealing and strength has been examined and different swaging methods have been investigated by finite element modeling methods. Based on the obtained results, the analysis methodology of ring swaging and the characteristic impact of swaging ring design on the sealing of pipe connection are shown. The prime novelty of the study is to report the impact of swaging...

Saudi Journal of Business and Management Studies, 2021

In the realm of beings, human beings by their nature, are never satisfied with one kind of produc... more In the realm of beings, human beings by their nature, are never satisfied with one kind of product and are always on the lookout for difference and innovation. When the world of animals is observed, for example, it can be seen that they are beings who never tire of eating grass or doing the same thing for life. Besides, they do not have multiple options. When the plants are observed, the situation looks similar; they consume soil for life and perform photosynthesis. Thanks to their mind and consciousness, people are equipped with the ability to compare, decide if they like or dislike, and want to pick or not pick the things they encounter. However, when these abilities face limited options, it's easy to get stuck in a difficult situation; They may also choose an option such as not preferring anything. It is also possible that they will search for an alternative. It is thought that the ability of people to prefer this or similar way may have a negative impact on customer loyalty to the brand and product. On the one hand, while producers want to increase their market shares by keeping the product range suitable for each consumer profile in terms of marketing, the consumer who faces the situation of choosing one among the diversity may have difficulty in choosing. For instance, which one of the cell phones, which of the televisions, which of the computers, which of the cars, etc. In fact, what is in question is how a product's design appeals to different consumer profiles in different ways. The customer buys a product whether he/she knows it and it fulfills his/her needs and aspirations, in other words, whether he/she likes it. Even if he/she does not purchase the product, he/she can preserve consumer loyalty by comparing the design innovations produced in the one he/she bought to the current version. However, when the customer cannot decide between different product designs that appeal to various customer profiles, he/she may lose his/her loyalty to the brand and switch to another product. This will have a detrimental effect on the product's marketing plan, and sales may decrease as a result. In this study, in terms of customer loyalty, the questions of: "Does a customer have the patience and time to choose without getting tired in the face of the variety of designs that appeal to different customer profiles in the same product?", "Will the customer still remain loyal?", "What solutions are there for the continuation of loyalty?" have been analyzed and researched. In other words, it was discussed what kind of relationship might exist between design and product diversity and customer loyalty. At the same time, the effect of low or no free time, unwillingness to collect information to evaluate products and to assess them for a long time on brand and product loyalty has been examined.

Saudi Journal of Engineering and Technology , 2021

Structural systems consist of subsystems and elements. Connection elements are needed for the sub... more Structural systems consist of subsystems and elements. Connection elements are needed for the subsystems and assembly and integration of these systems to the main system. Because the main system can fulfill its functional tasks when its assembly and integration with the subsystem is completed. Systematic static strength and dynamic behavior of structures, load bearing material and static cross-sectional properties as well as the strength and stiffness properties of the connections have a significant effect. The effect of the stiffness of the connection elements is higher in thin structural systems where the cross-sectional dimensions are much lower than the system dimensions. Assembly and integration are provided by using connection elements also in thin structural systems such as steel structure, scaffolding and rack structures. Therefore, the strength and stabilization of corner connections and fixing elements affect the entire system. However, while making systematic calculations, the structures, staying on the safe side, are modeled with rigid or rotatory hinged approach. When the connections are modeled as rotatory hinges, larger cross sections are required and support elements are added to prevent the system from becoming kinematic and collapse. With this approach, in buildings that require a lot of connection elements, the weight of the building increases too much and thus the cost increases. On the other hand, when the system is modeled with rigid approach, since the joints are unnecessarily excessively safe and the system's elasticity is very low, sudden overloads may result in collapse accidents and cause loss of life. For this reason, connection elements, especially in thin structures, must be modeled with real stiffness values and verified by tests under the prescribed loads. The purpose of this research is to examine the structural system design approach by modeling thin structure connection elements realistically and to create sensitivity in this regard. With this modeling method, it is aimed both to reduce costs and to prevent possible accidents caused by wrong modeling.

Journal of Materials Science and Technology, 2020

Friction stir welding is commonly used to join metals because it is environmentally friendly and ... more Friction stir welding is commonly used to join metals because it is environmentally friendly and provides higher fatigue strength than electric resistance spot welding, riveted connections, and screw connections. Alternative methods that do not reduce the fatigue strength, such as friction stir spot welding (FSSW), are being investigated. However, several studies have proven that FSSW joints are not sufficiently qualified for industrial usage. Defects such as keyholes, cavities, and cracks that form during classic FSSW with a screw stirring tool have not yet been eliminated. Some studies have demonstrated that the geometry of the stirring tool and the shoulder profile affect the quality of the joint. In this study, five pinless stirring tools with different shoulder profiles were designed to avoid the formation of cavities and cracks. The effect of the stirring tool on the mechanical properties and macro-and microstruc-tural material properties during the joining process were examined.

Materials Testing, 2020

To reduce the fuel consumption and enhance the flight performance of satellites, it is desirable ... more To reduce the fuel consumption and enhance the flight performance of
satellites, it is desirable to employ structural components of low weight,
high strength, and high stiffness. Therefore, most primary and secondary
structures of satellites are built using sandwich panels. Fasteners,
which constitute secondary structures, are normally used as joining
parts in different types of inserts such as partially potted, fully potted,
and through-thickness inserts. Finite element analysis (FEA) is valuable
for predicting the behavior of such primary and secondary structures.
However, to obtain more realistic results from such analysis, it is necessary
to define suitable fastener stiffness values. To this end, in this
study, a method for calculating the fastener stiffness of a fully potted
insert for sandwich panels using a finite element model is exemplarily
developed and experimentally validated. In addition, a shell modeling is
established for various connection types to further save time and reduce
the computational cost of the finite element model. Finally, the effects
of the fastener stiffness on the numerical analysis results for satellite
structural system are evaluated. The two-dimensional (2D) structure
modeling method used in this study was found to be as fully sufficient
as three-dimensional modeling. In addition to saving time and cost, 2D
FEA numerical modeling and prediction could reduce elaborate test costs.

Civil Engineering Journal, 2021

UHUK-2020-058, 2020

Merkezi silindir (MS) ler, özellikle haberleşme uydularında kullanılan tüm uyduyu taşıyan ana taş... more Merkezi silindir (MS) ler, özellikle haberleşme uydularında kullanılan tüm uyduyu taşıyan ana taşıyıcı yapısal elemanlardır. Daha fazla elektriksel güç, daha fazla faydalı yük ve daha uzun hizmet ömrü açısından daha yüksek kapasiteye uydular için uyduda daha fazla hacim oluşturmak ve etkili alan kullanımını gerektirir. Haberleşme uydularında geleneksel kimyasal itki sistemlerinde MS'in iç bölgesi yakıt tanklarını yerleştirmek için kullanılmaktadır. Teknolojik ilerlemeler sonucu elektriksel itki sistemleri kullanma eğilimi, daha küçük yakıt tankı gerektirmektedir. Dolaysıyla daha küçük hacimli merkezi silindir MS kullanılması durumunda faydalı yük kullanımı için daha fazla alan ve hacim sağlanarak uydu kapasitesi arttırılabilir. Bu çalışma, faydalı yük kullanımı için daha fazla alan ve hacim elde etmek için MS optimizasyonudur. Bu çalışmada tek veya üst üste konularak çoklu fırlatmaya uygun her iki uç kısımları eşit konik ve orta kısmı sabit çaplı düz silindirlerden oluşan MS in en az hacim için optimizasyon çalışması yapılmıştır. Orta sabit çaplı silindirden uç kısımlara geçişi sağlayan konik silindirlerin optimal açıları analitik olarak elde edilmiştir. Ayrıca elde edilen bu optimal geçiş acılı MS'lerin uzay aracı ve fırlatıcı isterlerine göre de değerlendirilerek tüm geometrik ve yapısal isterleri sağlayan en optimal MS elde edilmeye çalışılmıştır. Bu çalışma uydu ana taşıyıcısı olan MS tasarımında faydalı olacaktır. Daha detaylı çalışma için gerçek modellerin üretilip test edilerek teorik sonuçların gerçek modellerle doğrulanması önerilmektedir. Fakat bu tür yapısal elemanların üretimi ve testleri pahalı olduğundan küçük boyutlarda üretilip test edilerek çalışmanın doğrulanması mümkün olabileceği öngörülmektedir. GİRİŞ MS ler uydularda yüksek katılık, minimal kütle gibi ideal ana taşıyıcı yapısal eleman olmasının yanında içerisine yakıt tanklarının yerleştirilmesini mümkün kıldığı için ideal yapısal elemanlardır. Dışsal hacim olarak en büyük yapısal eleman olup genellikle uzunluğu uydu ana gövdesi uzunluğundadır. MS aynı zamanda uyduyu fırlatıcıya bağlayan ara-yüz elemanı olması nedeniyle fırlatıcıya bağlanan tarafı fırlatıcı ara-yüz adaptörü ile aynı yarıçaplıdır. Bu nedenle genellikle MS'ler fırlatıcı ara-yüz adaptörü çapıyla aynı olacak düz veya fırlatıcıya bağlantı tarafı konik, üst kısmi düz silindir olacak şekilde yapılırlar(Şekil 1). Tablo-1 de fırlatıcıların kullandıkları arayüz adaptör çaplarını göstermektedir[Falcon X 2020, Proton, 2020, Araine 5, 2020]. Haberleşme uydularında en yaygın olarak 937 mm ve 1194 mm çaplı adaptörler kullanılmaktadır. Bu nedenle bu çalışma dada 937 mm ve 1194 mm lik adaptörler sonlu elemanlar modellerinde ve analitik uygulamalarda kullanılacaktır.

ÖZET Alüminyum ve magnezyum alaşımları gibi hafif metaller kara taşıtlarında, elektronik, bilgisa... more ÖZET Alüminyum ve magnezyum alaşımları gibi hafif metaller kara taşıtlarında, elektronik, bilgisayar ve spor gereçleri endüstrisinde kullanım alanları bulmaktadır. Özellikle otomotiv ve havacılık endüstrisinde ağırlık kazancı ve dolayısıyla yakıt tüketiminin azaltılması amacıyla yeni, düşük ağırlıklı mühendislik malzemelerinin geliştirilmesi konusunda birçok çalışma yapılmaktadır. Bu alanda çalışılan metallerden biri düşük yoğunluğu ile (alüminyumdan % 35, titanyumdan % 65 daha hafif) magnezyumdur. Metal alaşımlarının ergitme esaslı kaynak yöntemleri ile birleştirilmelerinde problemler yaşanmaktadır. Ergitme kaynak yöntemleri ile hafif metal levhaların birleştirilmesi zor olması nedeni ile birleştirmelerde sıklıkla Sürtünme Karıştırma Kaynağı (SKK) yöntemi kullanılmaktadır. Bu çalışmada, sürtünme karıştırma nokta kaynağı yöntemi ile 1,5 mm kalınlığından magnezyum levhalar birleştirilmiştir. Birleştirme yöntemde kullanılan pimin omuz tasarımları üzerinde araştırma yapılarak, beş farklı omuz tasarımı ile magnezyum levhalar SKNK yöntemi birleştirilmiş ve bu kaynaklı bağlantıların mekanik özelliklerinden çekme-makaslama ve eğme dayanımı incelenmiştir. Anahtar Kelimeler: Vidasız sürtünme karıştırma nokta kaynağı, Alüminyum ve Magnezyum kaynağı, Hafif metallerin punta kaynağı, Sürtünme karıştırma nokta kaynağı.
ABSTRACT Light metals such as aluminum and magnesium alloys are used in land vehicles, electronics, computers, and sports device industry. Many studies have been carried out on the development of new, low weight engineering materials to reduce weight and fuel consumption, especially in the automotive and aerospace industries. One of the first metals that comes to mind in this area is magnesium with low density (35% from aluminum and 65% lighter than titanium). In addition to these advantages, there are problems in combining light metal alloys with melting-based welding methods. Frequently, Friction Stir Welding (FSW) as a melt welding method is difficult to join of light metal plates. In this study, magnesium plates were joined with 1.5 mm thick by friction stir spot welding (FSSW). Different shoulder designs of FSSW-Tool have been designed, used in joining with FSSW-Method and researched their ability to join. Five different shoulder designs were used to join the magnesium sheet with FSSW and were investigated the tensile-shear and bending strengths of these welded joints.

— In this paper, friction stir spot welding (FSSW) of magnesium sheets were analyzed using finite... more — In this paper, friction stir spot welding (FSSW) of magnesium sheets were analyzed using finite element method (FEM). Various tool shoulder types used in Friction stir welding (FSW) were chosen as different parameter. Thermic simulations were showed that thermic conditions vary with tool shoulder design types used in friction stir welding. Heat energy input (Q) of numerical model was solved analytically and calculated based on the various parameter values. Friction factor surface pressure and materials thermic properties which are changing with generated heat during friction welding were also considered in the FEM analysis. Thermic field model was solved numerically and results were presented. Index Terms— Friction stir spot welding (FSSW), Tool tip shoulder profile design, Magnesium welding, Thermal analysis of FSSW.

International Journal of Engineering and Applied Sciences (IJEAS), 2018

 Abstract— In this paper, friction stir spot welding (FSSW) of magnesium sheets were analyzed us... more  Abstract— In this paper, friction stir spot welding (FSSW) of magnesium sheets were analyzed using finite element method (FEM). Various tool shoulder types used in Friction stir welding (FSW) were chosen as different parameter. Thermic simulations were showed that thermic conditions vary with tool shoulder design types used in friction stir welding. Heat energy input (Q) of numerical model was solved analytically and calculated based on the various parameter values. Friction factor surface pressure and materials thermic properties which are changing with generated heat during friction welding were also considered in the FEM analysis. Thermic field model was solved numerically and results were presented. Index Terms— Friction stir spot welding (FSSW), Tool tip shoulder profile design, Magnesium welding, Thermal analysis of FSSW.

Eurocode 3 (EC3) was introduced in the European Community countries of June 2012. Previously the ... more Eurocode 3 (EC3) was introduced in the European Community countries of June 2012. Previously the weld connection of steel structure was calculated with different methods (DIN 18800) in different countries. With TS EN 1993-1-1-December 2005-" design of steel structures, " and TS EN 1993-1-8+AC-December 2005-" General Rules-design of joints named " has Turkey joined to it. EC3; include the design of steel structures, production, quality, installation and calculation methods. Welded connection design principles and calculation methods, which is our topic EC3-8 (EN 1993-1-8 " design of steel structures: design of joints ") is located, includes some innovative methods. In this study, it is resourced the methods of weld design and analysis of steel structure connections according to EC3. The 5. group referenced in welding consumables, welding geometry, dimensions and boundary methods for the calculation of the resistance forces are emphasized. The most used weld type is filet weld. The methods of calculation and dimensioning of this welding type were investigated and there are given examples for the implementation of this standart in order to assist the use in Turkey.

Eurocode 3 (EC3) was introduced in the European Community countries of June 2012. Previously the ... more Eurocode 3 (EC3) was introduced in the European Community countries of June 2012. Previously the weld connection of steel structure was calculated with different methods (DIN 18800) in different countries. With TS EN 1993-1-1-December 2005-“design of steel structures,” and TS EN 1993-1-8+AC - December 2005-“General Rules-design of joints named” has Turkey joined to it. EC3; include the design of steel structures, production, quality, installation and calculation methods. Welded connection design principles and calculation methods, which is our topic EC3-8 (EN 1993-1-8 “design of steel structures: design of joints”) is located, includes some innovative methods. In this study, it is resourced the methods of weld design and analysis of steel structure connections according to EC3. The 5. group referenced in welding consumables, welding geometry, dimensions and boundary methods for the calculation of the resistance forces are emphasized. The most used weld type is filet weld. The methods of calculation and dimensioning of this welding type were investigated and there are given examples for the implementation of this standart in order to assist the use in Turkey.

Conference Presentations by Ahmet Atak

Machine parts fail to perform their tasks due to the fatigue with the rate of 90%. The fatigue ap... more Machine parts fail to perform their tasks due to the fatigue with the rate of 90%. The fatigue applications have been known since the early days of the industrial revolution. The field of study on metal fatigue has started to expand due to the increase in the use of steel constructions in the systems of railway bridges in particular. It is of critical importance for all of the engineering fields to produce designs against the fatigue. Moreover, it is quite difficult to determine the initial damages of the fatigue by way of observation and the initial damages of the fatigue cannot be mostly recognized until a structural component becomes unusable. Therefore, the determination of fatigue life of the structural members during the stage of design and development results in a considerable decrease in unexpected damage risk that may occur during the use. Thus, reliable methods which can accurately predict the fatigue life are required. However, it is very difficult to find one single method to determine the fatigue life because of the presence of different loads and different designs. Finding a generally accepted and unified method which can accommodate to the desired condition removes difficulties in determining the fatigue life for each of the designs separately and facilitates the design process against the fatigue. The fatigue strength is normally found by means of " Wöhler method ". It is also called as the method of (S-N) curves. In this method, each of test parts which are completely same in terms of material, shape and the quality of surface are continually forced to the stress at different levels and the number of cycles with which the fracture occurs is determined. In this study, a bending fatigue strength machine was designed in accordance with the method of Wöhler curve. A linear motor enabling a linear movement was used in the bending fatigue testing machine. The designed bending fatigue machine was different from the existing machines in terms of not occupying much area, noise being lower, non-requirement of the additional apparatus (strap, camshaft, etc.) as the movement is linear; determination of the force applied on the test sample directly in computer software and easiness of the measurement and obtaining data such as on which life number the test sample fractured.

PROGRAMS PROCEEDİNGS POSTERS SPONSERS

Makina parçalarının görevlerini yapamamalarının % 90 nedeni yorulmadan dolayıdır. Yorulma, yüzey ... more Makina parçalarının görevlerini yapamamalarının % 90 nedeni yorulmadan dolayıdır. Yorulma, yüzey düzgünlüğünü bozan çentik, keskin köşe, girinti, çıkıntı vb. gibi yüzey kusurlarından ya da içyapı içinde eşdağılımlılığı bozan katışkı, kalıntı, kılcal çatlak, keskin uçlu çökelti ve parçacıklardan kaynaklanabilir. Eurocode 3 (EC3) standardında çelik yapı sistemlerine tüm tahkik hesapları için çeşitli laboratuvar ve saha testleriyle desteklenmiş yöntem yenilikleri geliştirilmiştir. EC3, 2012 yılından beri tüm Avrupa ülkelerinde çelik yapılarda dikkate alınması zorunlu kılınmıştır. TSE tarafından da Türkiye’de aynen uygulanması bakımından TS EN 1993-1, 2,… şeklinde alınarak geçerli hale gelmiştir. EC3 Bölüm 9’da (EC3-9) yorulma dayanımı gereksinim, hesap ve tahkik yöntemlerini işlemektedir. Bu araştırma kapsamında genel olarak kaynaklı bağlantıların yorulma dayanımı ile ilgili kısımları incelenmiştir. Kaynaklanan bölgede oluşan çentik etkisi sebebiyle yorulma dayanımı çok önemli derecelerde etkilenmektedir. Bağlantı çeşitlerine bağlı verilen çentik faktörü kataloglarının analiz edilip, daha iyi anlaşılmasına katkıda bulunmak araştırmanın bir diğer amacını oluşturmuştur. Kaynaklı birleştirmelerde yaygın olarak kullanılan köşe birleştirmelere ait örnek hesaplamalar yapılmıştır. Böylece kaynaklı bağlantıların yorulma ömürlerinin kolayca EC3’e göre hesaplanmasının ulusal olarak yaygınlaşmasına katkıda bulunulmuştur.
The main reason to finish the mission of machine parts is based with 90 % of the fatigue. Fatigue can be caused by surface defects with smoothness, sharp corners, indentations, protrusions, etc. One other sort of effect of fatigue the defects in the microstructure like ruins, cracks, sharp and sediment particles. Eurocode 3 (EC3) method has been developed in order to verify the standard of steel structures for all accounts innovations that is supported by various laboratory and field tests. Since 2012, EC3 is obliged to take into account for the steel structure all over European countries. Turkey taken over the standard EC3 equally to become available their use by the form TS EN 1993-1, 2,…. The EC3-Chapter 9 (EC3-9) handled the fatigue calculation with requirements and verification methods. In this research area it has been examined in general the parts of welded joints. Another purpose of this research was to contribute to a better understanding of fatigue life analysis. The notch effect (Sharply factor) is very important parameter of the fatigue of welded connection parts. In order to improve understanding of fatigue analysis are given some commonly filet welded joining Examples. One other target was to contribute to the nationally spread of the method of the fatigue life analysis according to EC3 for the welded connections easily.

Universal Journal of Mechanical Engineering, 2019

Aluminium Alloys - Design and Development of Innovative Alloys, Manufacturing Processes and Applications [Working Title]

Universal Journal of Mechanical Engineering

Civil Engineering Journal

Saudi Journal of Business and Management Studies, 2021

Saudi Journal of Engineering and Technology , 2021

Journal of Materials Science and Technology, 2020

Materials Testing, 2020

Civil Engineering Journal, 2021

UHUK-2020-058, 2020

International Journal of Engineering and Applied Sciences (IJEAS), 2018

Eurocode 3 (EC3) was introduced in the European Community countries of June 2012. Previously the ... more Eurocode 3 (EC3) was introduced in the European Community countries of June 2012. Previously the weld connection of steel structure was calculated with different methods (DIN 18800) in different countries. With TS EN 1993-1-1-December 2005-“design of steel structures,” and TS EN 1993-1-8+AC - December 2005-“General Rules-design of joints named” has Turkey joined to it. EC3; include the design of steel structures, production, quality, installation and calculation methods. Welded connection design principles and calculation methods, which is our topic EC3-8 (EN 1993-1-8 “design of steel structures: design of joints”) is located, includes some innovative methods. In this study, it is resourced the methods of weld design and analysis of steel structure connections according to EC3. The 5. group referenced in welding consumables, welding geometry, dimensions and boundary methods for the calculation of the resistance forces are emphasized. The most used weld type is filet weld. The methods of calculation and dimensioning of this welding type were investigated and there are given examples for the implementation of this standart in order to assist the use in Turkey.

PROGRAMS PROCEEDİNGS POSTERS SPONSERS

The use of light metals today is of great importance, for example in the automotive, aviation and... more The use of light metals today is of great importance, for example in the automotive, aviation and aerospace industries, where energy consumption is minimized and thus the economy is being attempted. By using light metals, weight is reduced so that energy is saved. Aluminum and magnesium alloys are particularly used thanks to their lightweight. Vehicles in the automotive, aerospace and space industries are expected not only to have lightweight but also high static and dynamic strengths since they are exposed to static and dynamic cyclic loads.
However, the structural components can quickly become fatigued and fail under cyclic load due to the notch factor of the joining zones. Compared to the fusion welding method, joining of material is realized mechanically below the melting point of the material in the friction stir spot welding (FSSW) method. Thus, the fatigue strength of the assembly is much higher than that of the fusion welding.
In this study, Light metal alloy of magnesium AZ31B and aluminum EN AW 2024 were joined with FSSW method and mechanical properties of this joins were also carried out.

The Light metals such as aluminum and magnesium alloys find extensive use in land and air transpo... more The Light metals such as aluminum and magnesium alloys find extensive use in land and air transport vehicles, electronics, computer and sporting goods industries. In order to reduce weight and thus save fuel, many studies are carried out on the development of new engineering materials, which have lightweight and high fatigue strength, especially for the automotive and aviation industry. One of the first metals remembered in this field is magnesium, which has lower density. In contrary to these advantages, joining of light metal alloys with fusion based welding methods have some problems. Since the fusion welding of light metal sheets is difficult, friction stir welding (FSW) method frequently used for joining of these. Studies has shown that shoulder profile of welding tool, which apply pressure on material, affects the welding quality in FSW method. In order to understand these effects various shoulder profile has been studied and understood.
FSW method has been investigated and used for joining of materials since about 50 years. In this paper, the pinless shoulder profile designs of stir tool and the mechanical properties and fatigue strength of magnesium and aluminum alloy sheets, which are joined with these stir tools, are aimed to investigate. In order to realize this, shoulder profiles were designed and manufactured accordingly. Subsequently, magnesium and aluminum alloy sheets for automotive and aviation applications were joined with friction stir spot welding (FSSW). Finally, mechanical properties of joined materials such as tensile, tensile shear, bending and fatigue strength were tested.
As a result, it has been verified that light metal alloys such as magnesium alloy AZ31B with good ductile and fatigue strength can easily be joined with FSSW. Moreover, joining of light metals with FSSW method has been demonstrated with comparative test and analysis in engineering applications.