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Geniş kullanım olanağı bulunan ve birçok fayda sağlayan nitrasyon işleminin östenitik paslanmaz çeliklerin kaynak işlemiyle birlikte ele alındığı, “AISI 304L Paslanmaz Çelik Malzemelerin Lazer Kaynağıyla Birleştirilmesinde Nitrasyon İşleminin Mikroyapı ve Mekanik Özelliklere Etkisinin Araştırılması” başlıklı bu çalışmada; otomotiv, uzay, havacılık, sağlık, gıda ve savunma gibi birçok alanda kullanılan östenitik paslanmaz çeliklerin lazer kaynağıyla birleştirilmesi ve nitrasyon işleminin lazer kaynağına etkileri araştırılmıştır. Lazer kaynak yöntemiyle, 3 farklı güç parametresinde birleştirilen AISI 304L östenitik paslanmaz çelik numunelere yapılan mekanik testlerde optimum sonuçların 1500 Watt güç ile birleştirilmiş numunede olduğu görülerek, aynı parametrede benzer numunelere kaynak işlemiyle birlikte, kaynak öncesi ve sonrası olmak üzere nitrasyon işlemleri uygulanmıştır. Test ve incelemeler sonucunda tüm numunelerde kaynak nüfuziyetinin istenildiği şekilde oluştuğu, kaynaklı birleştirmenin penetrasyonunun uygun olduğu, ana malzeme mikroyapılarının eş taneli östenitik paslanmaz çelik mikroyapısına benzediği, kaynak metalinde kaynak merkezine doğru yönlenen dendritik ve sütünsal yapıların oluştuğu, ITAB’ın ise lazer kaynağının karakteristik özelliği olarak dar bir bölgede oluştuğu tespit edilmiştir. Optimum parametrede kaynak ve nitrasyon işlemleri gerçekleştirilen numunelerin mukavemet ve uzama değerleri 2 numaralı deneye yakın değerler gösterse de en yüksek çekme testi sonuçları 2 numaralı deneyde tespit edilmiş, tüm kopmalar ITAB bölgesinde meydana gelmiştir. Eğme testleri sonucunda; kaynaklı birleştirmelerin numunelerin sünekliğine tesir edecek herhangi bir olumsuzluk içermediği, ana malzemeye benzer süneklik sergilediği anlaşılmıştır. Mikrosertlik incelemelerinde; en yüksek mikrosertlik sonuçları ITAB’da olmak üzere; nitrasyon işlemi yapılarak birleştirilen 4 ve 5 numaralı deneylerin mikrosertlik değerlerinin, nitrasyon işlemine tabi tutulmadan birleştirilen 1, 2 ve 3 numaralı deneylerden daha yüksek olduğu tespit edilmiştir.

In this study, we performed experimental and statistical analysis on the cutting of AISI 304 stainless steel using a commonly utilized laser cutting machine. Three different gas pressures (5.1, 6.4 and 8 bar), three different cutting speeds (2048, 2560 and 3200 mm/min), fixed focal point (-4 mm), fixed frequency (5000 Hz) and fixed gas (Nitrogen) were used as cutting parameters. As a result of the study, it was observed that the surface roughness decreased as the cutting speed increased at all pressure values, and the surface roughness increased as the pressure increased at all cutting speed values. It was determined that the top and bottom kerf width decreased with increasing cutting speed and decreasing gas pressure, and the top and bottom kerf width increased with increasing gas pressure and decreasing cutting speed. When the signal/noise ratios were analyzed as a result of Taguchi analysis, the optimum cutting parameter was calculated as Level 1 (5.1 bar) for pressure and Level 3 (3200 mm/min) for cutting speed. When the variance results were analyzed, it was determined that the important parameter affecting the surface roughness from the pressure and cutting speed factors was determined as cutting speed with 70.74%. [ABSTRACT FROM AUTHOR]

Copyright of Gazi Üniversitesi Fen Bilimleri Dergisi Part C: Tasarım ve Teknoloji is the property of Gazi University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Stainless steel is the most used metal all over the world. Since the corrosion resistance of steel is low in acidic medium and the use of acid in industry is very common, it is important to protect the steel from corrosion. In this study, the environmentally friendly nicotinamide compound was used as an inhibitor to protect steel from corrosion. In the study, firstly, the cyclic voltammetry technique was used to determine the electrochemical behavior of the steel in 0.1 M HCl acid solution. Then, Tafel Polarization Method in 0.1 M HCl acid solution was applied to determine the corrosion behavior of steel in the absence of nicotinamide inhibitor, in the presence of 500 ppm, 750 ppm and 1000 ppm nicotinamide. The optimum time was determined for each concentration by keeping the inhibitor at these 3 different concentrations for 0, 15, 30, 45 and 60 minutes. The highest inhibitory efficiency was found to be 96.8% in 1000 ppm nicotinamide concentration in 15 minutes holding time, and 96.6% at 500 ppm nicotinamide concentration in 60 minutes holding time in the absence of time limitation. The results obtained showed that nicotinamide can be used effectively in the protection of stainless steel from corrosion, and due to its environmental friendliness, corrosion protection is provided while not harming the environment and living things. [ABSTRACT FROM AUTHOR]

Bu çalışmada, kuru frezeleme koşullarında üç farklı takım geometrisine sahip CVD TiAlN/Al2O3/TiCN kaplı karbür uçlar kullanılarak AISI 316L’nin yüzey bütünlük özelliklerini değerlendirmek için Taguchi yöntemi uygulanmıştır. Bir CNC tornada ortogonal dizili bir deneysel tasarım olan L18 (2x3x3x3) kullanılarak çeşitli deneyler yapılmıştır. İşleme parametrelerinin ortalama yüzey pürüzlülüğü, çevresel ve eksenel yüzey kalıntı gerilmeleri ve işleme sertleşmesi derecesi üzerindeki etkilerini belirlemek için varyans analizi (ANOVA) kullanıldı. İşleme parametreleri olarak kesme derinliği, kesici takım geometrisi, kesme hızı ve ilerleme hızı seçilmiştir. İşleme parametrelerinin kalite özellikleri üzerinde farklı etkileri olduğu görülmüştür. Kesme derinliği, yüzey pürüzlülüğü üzerinde nispeten etkili bir parametreydi ve diğer kalite özellikleri üzerinde önemli bir etkisi yoktu. Takım geometrisi ortalama yüzey pürüzlülüğünü etkilemedi. Ancak sırasıyla sertleşme derecesi, çevresel ve eksenel yüzey kalıntı gerilmeleri üzerinde daha etkili olmuştur. Kesme hızının sırasıyla eksenel ve çevresel yüzey kalıntı gerilmeleri ve sertleşme derecesi üzerinde daha önemli bir etkiye sahip olduğu belirlendi. İlerleme hızı, yüzey pürüzlülüğü üzerinde çok yüksek bir etkiye sahipken, sırasıyla çevresel ve eksenel yüzey kalıntı gerilmeleri ve sertleşme derecesi üzerinde de önemli bir etkiye sahip olduğu görülmüştür.

The additive manufacturing method has been developed and continues to be investigated as an alternative to conventional manufacturing methods. This method is based on part production from 3D computer aided software. Additive manufacturing, also called a three-dimensional (3D) printing technology, is divided into two sections as powder and wire according to the type of used material. Powder-based system, the powder accumulated on the metal substrate; parts are produced by melting or sintering them with electron, laser, or arc heat source. In wirebased system, the method of melting and depositing the wire material using MIG / MAG, TIG or plasma welding systems is used. In this study, Wire arc additive manufacturing (WAAM) method is explained and classified according to the type of heat source. This method has become an important research topic for the industry with its advantages, such as reductions in production time, production close to net shape and cheapness of wire raw material compared to powder. In this study, research about stainless steel, aluminium, nickel super alloys, magnesium, and Ti6Al4V alloys which are used commercially in industry were reviewed. Mechanical properties were compared with traditional manufacturing methods such as casting and forging. It has been noted that the cooling conditions for steel alloys are important for mechanical properties obtained in the productions. It has been determined for aluminium alloys that the processes performed during or after production (rolling, forging, etc.) positively affect mechanical properties. In addition, it has been seen that the desired mechanical properties can be achieved for Ti6Al4V alloys. [ABSTRACT FROM AUTHOR]

Copyright of Dokuz Eylul University Muhendislik Faculty of Engineering Journal of Science & Engineering / Dokuz Eylül Üniversitesi Mühendislik Fakültesi Fen ve Mühendislik Dergisi is the property of Dokuz Eylul Universitesi Muhendislik Fakultesi Fen ve Muhendislik Dergisi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Gazi Üniversitesi Fen Bilimleri Dergisi Part C: Tasarım ve Teknoloji is the property of Gazi University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this study, the effects of cutting tool height adjustment on cutting force components in turning were investigated. The experiments were carried out on a CNC lathe using AISI304 stainless steel material, which is a reference material. In the experiments, carbide inserts with a SNMG form were used. The cutting tools were tested for three different levels: at the part axis (0 mm), above of the part axis (+0.5 mm), and at below of the part axis (-0.5 mm). Moreover, three different cutting speeds (100, 150 and 225 m/min), three different feeds (0.15, 0.25 and 0.35 mm/rev), three different depths of cut (0.8, 1.3 and 2 mm) and two different insert radius (0.4 and 0.8 mm) were considered into experiments. Cutting force components (Fc, Ff, Fr) were measured instantaneously with a standard dynamometer. Taguchi and ANOVA analysis were done to figure out the effect of the setting of the cutting tool height on the cutting forces. As a result of the evaluation, it is seen that the cutting forces were obtained lower when the cutting tool is adjustment at the part axis and above of the part axis. Otherwise, the cutting forces were measured higher, while the setting the height of cutting tool is at below of the part axis. As the depth of cut and feed rate increased in the experiments, the effect of cutting tool height adjustment on cutting forces also increased. The parameters that are the depth of cut and the feed rate were identified the major effect on the cutting forces. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the corrosion behaviour of annealed stainless steel mesh. Thermal oxidation treatments were applied to steel mesh in a muffle furnace at 500 ᵒC, 700 ᵒC and 900 ᵒC. Surface morphology of annealed and non-annealed stainless steel meshes was compared before and after polarization. Roughness of the steel surface was increased after heat-treatment. The corrosion properties of non-annealed and annealed steel were determined using linear sweep voltammetry. The corrosion behaviour of annealed stainless steel was examined by means of a potentiostat in a 3.5 wt.% NaCl, 1 M H2SO4 and 1 M KOH electrolytes. The corrosion susceptibility of heat treated stainless steel was more than that of non-heat treated stainless steel in alkaline electrolyte. While pitting corrosion of non-annealed and annealed stainless steel was different, corrosion potential and current of steel mesh without heat treatment was the same as the steel meshes annealed at 500 ᵒC and 700 ᵒC. Corrosion current and corrosion potential of non-annealed steel was the same as 500 ᵒC annealed steel mesh in acidic medium.

Bu çalışmanın amacı, ferritik ve östenitik paslanmaz çeliklerin ilave yapıştırıcı kullanarak elektrik direnç nokta kaynak yöntemi ile birleştirilmesi esnasında değiştirilen bazı kaynak parametrelerinin mekanik ve mikroyapı özelliklerine etkisini araştırmaktır. Çalışmada, AISI 430 ferritik ve AISI 304L kalite östenitik paslanmaz çelikler nokta direnç kaynak yöntemi ile yapıştırıcılı ve yapıştırıcısız olmak üzere birbirleri ile birleştirilmiştir. Kaynak işlemleri; 5, 8, 11 kA kaynak akımı ve 10, 20, 30 periyot kaynak süresinde olmak üzere 9 farklı parametrede yapıştırıcılı ve yapıştırıcısız olarak 2 farklı şekilde gerçekleştirilmiştir. Yapıştırıcılı kaynak numunelerinde Tereson MS 9220 yapıştırıcı malzeme kullanılmıştır. Yapılan deneysel çalışmalar sonucunda; kaynak akımının artması ile buna paralel olarak kaynak çekirdek çapı ve elektrot dalma derinliği artmıştır. İlave yapıştırıcı kullanılan yapıştırıcılı numuneler yapıştırıcısız numunelere göre daha fazla çekme-makaslama dayanımı sağladığı gözlemlenmiştir. Sertlik deneyleri sonucunda en yüksek değerler kaynak çekirdeğinden ölçülmüştür. Mikroyapı görüntüleri incelendiğinde östenitik kısımlarda yüksek ısı girdisinden dolayı kaynak çekirdeğinde oluşan tanelerin irileştiği gözlemlenmiştir.

Copyright of Journal of Health Sciences / Sağlık Bilimleri Dergisi is the property of Erciyes Universitesi Saglik Bilimleri Dergisi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Günümüzde lazer ışını ile kesme yöntemi modern malzeme kesme yöntemleri arasında maliyet ve kalite açısından üstün özellikleri nedeni ile öne çıkmaktadır. Özellikle lazer kesme yöntemi, imalat sektöründeki birçok uygulamada kullanılan paslanmaz çeliklerin kesilmesinde çok önemli avantajlara sahiptir. Bu çalışma kapsamında 304 kalite paslanmaz çelik malzemenin fiber lazer ile kesilmesinde lazer gücü, kesme hızı ve odak mesafesinin kesilen yüzeylerin pürüzlülüğü ve kerf genişliği üzerindeki etkileri incelenmiştir. Box-Behnken deney tasarımına göre parametre çiftleri belirlenerek kesme işlemi gerçekleştirilmiş ve yüzey pürüzlülükleri ile kerf genişlikleri ölçülmüştür. İşlem parametrelerinin tekil ve etkileşimli etkilerini belirlemek için varyans analizi (ANOVA) uygulanmıştır. Yüzey pürüzlülükleri ve kerf genişlikleri için cevap yüzeyi fonksiyonları belirlenmiş ve istenebilirlik fonksiyonu yaklaşımı ile optimum proses parametreleri tespit edilmiştir. Yapılan çalışma sonucunda yüzey pürüzlülüğü ve kerf genişliği üzerindeki en etkili parametrenin odak mesafesi olduğu, ilerleme hızının etkisinin sınırlı kaldığı görülmüştür.

Kriyojenik işlem malzemelere uygulanan ve malzemelerin tribolojik özelliklerini geliştiren ve geleneksel ısıl işlemi tamamlayıcı veya geleneksel ısıl işleme alternatif ucuz bir ısıl işlemdir. Malzemelere uygulanan kriyojenik işlemin, kalıntı östeniti martenzite dönüştürdüğü, daha homojen mikroyapı sağladığı, aşınma direncini, sertlik ve elektrik iletkenliğinde artış sağladığı bilinmektedir. Bu çalışmada sığ kriyojenik işlemin AISI 410 paslanamaz çeliğin mikroyapısına, sertliğine ve elektrik iletkenliğine etkisi araştırılmıştır. Sığ kriyojenik işlem 4 farklı (24, 48, 72 ve 96 saat) bekleme sürelerinde uygulanarak bekleme süresinin etkisi tespit edilmiştir. İşlem görmemiş numuneler (N0) referans alınarak sonuçlar değerlendirilmiştir. Elde edilen sonuçlara göre sığ kriyojenik işlemin AISI 410 paslanmaz çeliğin mikroyapısını düzenleyerek homojen hale getirdiği gözlemlenmiştir. Sığ kriyojenik işlem N4 numunenin sertliğini, N0 numuneye göre yaklaşık %4 arttırmıştır. Ayrıca elektrik iletkenliğinde %300 artış sağlanmıştır. Sertlik ve elektrik iletkenliğine en fazla etki 96 saat bekleme süresinde elde edilmiştir. Genel olarak sığ kriyojenik işlemin, uygun bekleme süresinde, paslanmaz çeliğin sertlik ve elektrik iletkenliğine olumlu etkiye sahip olduğu görülmüştür.

Nii3Al intermetallic compound was coated on the ferritic stainless steel surface using the combustion method. Effects of the compacting pressure (150, 200, 250 and i300 MPa) and the sintering temperature (1100 °C) on the coated layer were investigated. Characterization of the coating layer was performed using optical microscope, SEM, XRD and EDX analyzes. As a result of the analysis, it was observed that the bonding quality between the coating layer and the base metal was good due to the diffusion. As a result of EDS analysis α Fe, Cr, Ni, Nii3Al, analiz Fe and in the XRD results, Nii3Al4, NiAl, Nii3Cr2, Ni2Ali3 phases were formed with Nii3Al and Ni. In the microhardness analysis, due to the porous structure of the coating layer, the results were lower than the base metal. However, it has been determined that the sintering temperature of 1100 °C is better for complete dissolution of semi-stable intermetallic phases. [ABSTRACT FROM AUTHOR]

Copyright of Turkiye Klinikleri Journal of Dental Sciences is the property of Turkiye Klinikleri and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Implant Dentistry is the property of Lippincott Williams & Wilkins and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Laser welding is a special method and also still developing. Melting of materials is based on the principle that high-energy rays are used in the merge. High-energy rays reflected on a combined material at any desired ratio and successful welding process can be performed. Low heat input with narrow HAZ region, the possibility of low distortion, deep penetration and high strength due to the properties of choice laser welding in the automotive industry is of great importance. In this study, the effect of the geometry on the seam of laser welding parameters of high alloy stainless steel used in the automotive industry were investigated. [ABSTRACT FROM AUTHOR]

Copyright of Afyon Kocatepe University Journal of Science & Engineering / Afyon Kocatepe Üniversitesi Fen Ve Mühendislik Bilimleri Dergisi is the property of Afyon Kocatepe University, Faculty of Science & Literature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Low heat input, narrow HAZ, low stress strain and distortion, high welding speed, high penetration, smooth welding sections, high structural strength and automatic process are primary advantages of the laser welding. Moreover high efficiency and being economical leading less error rates are other advantages. In this work AISI 304, 50x40 mm stainless steel test items with 2,0 mm thickness were but laser welded. These 20x80 mm test items were tested in guidance with metallographic investigation, measuring hardness, three point bending test performed as explained in TS 282 EN 910 standards. According to the results, the solidified weld metal has the form of keyhole and full penetration has been determined. With increase of welding speed, weld width and depletion width between weld metal and base metal decrease. Hardness of the weld metal is getting higher from base metal to depletion zone. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to determine the relationship between the accuracy of the Root ZX apex locator and conductivity of hand files. Material-Method: In this study, 47 extracted maxillary anterior teeth were used. Each tooth was mounted in an alginate model so that an electronic apex locator could be used to measure canal length with four different hand ISO 15 K-file groups. Four groups were established which consist of a different type file. All file groups were tested for electrical conductivity using the four-point probe method. The relationship between the accuracy of Root ZX and electrical conductivity of the files was analysed with Kruskal Wallis at a significance level of 0.05. Duncan's Multiple Range Test was used to detect the differences between the groups. Results: Whilst 34% of samples were short of the control working length, the highest conductivity values were obtained in Group 2 (p < 0.05). Discussion: For the conductivity results, there was a correlation between accuracy of the Root ZX apex locator and the conductivity of hand files. However clinical trials that involve further apex locators and files of observations are needed. [ABSTRACT FROM AUTHOR]

In this study, porous surfaces made of SS316L spherical stainless steel powder have been produced to be used in heat exchangers of fuel cells by designing and producing forming die and special punches. Minimum pressure and temperature levels for compacting have been examined to obtain sufficient bonding between powders and the substrate. Moreover, surface roughness of the substrate has been increased in order to bond substrate and the powders. Surface etching techniques have been investigated and minimum surface roughness of the substrates has been defined. Besides, the effects of temperature and pressure on open porosity have been investigated. The experiments and the tests showed that 200 MPa compacting pressure, 500°C temperature and Ra=1.7 µm roughness, on the substrate are enough to realize such surfaces. Under these circumstances 29.6% porosity has been obtained. [ABSTRACT FROM AUTHOR]

Austenitic stainless steels represent an important class of materials which possess excellent cryogenic properties and good high-temperature strength. Their mechanical properties are comparable to those of mild steels but offer an excellent general corrosion resistance in the atmosphere, in many aqueous media and oxidizing acids. Particularly, the addition of molybdenum in type 316L provides pitting resistance in phosphoric and acetic acids and chloride solutions, as well as corrosion resistance in sulphurous acid. However, in general, stainless steels are characterized as having relatively poor wear resistance. This fact has led to the development of a number of surface treatments in order to improve their tribological performance without compromising their corrosion resistance, such as nitriding by ion implantation, pulsed plasma nitriding and plasma immersion ion implantation, boronizing. Also, it has been well documented that it is possible to extend the service life of many different parts and components, made of relatively soft substrates, subjected to corrosion and wear, by means of the use of thin hard films such as oxides, nitrides and carbides applied onto their surfaces. However, since such parts could also be subjected to cyclic loading during service, it is of almost importance to evaluate the effect of such hard films on the fatigue properties of the coated substrate, an area which has become an important research topic in the past few years. Mainly, AISI 316 L type steels are used in biomedical applications, automotive industry, ship industry, HVAC (heat ventilation air condition climate) systems and pressure vessel systems. Different superficial hardening processes are commonly applied to metals. Those are generally limited by the metal's original chemical composition as well as the required mechanical properties. Thermochemical methods, for which the superficial composition is locally modified, can produce microstructures and mechanical properties that are completely different from those of the basic metal. atoms and those of the basic metal leads to the formation of new compounds in the superficial layer. Boriding or boronizing is a thermochemical surface hardening technique used for boridetype coating that can be applied to a large range of materials (ferrous metals, non-ferrous metals and cermets). Boriding can be performed in numerous ways, including gas boriding, molten salt boriding, with and without electrolysis, and pack boriding. The produced layers provide an extremely high hardness, good tribological properties and anti-corrosion resistance of the treated surfaces. It is a surface treatment process in which boron atoms are diffused into the material surface between 800 and 1100 °C. A boride layer with hardness (HV) of 1600-2000 forms by penetrating and diffusing boron to the surface. Boronizing is a prominent choice for a wide range of tribological applications where the control of friction and wear is of primary concern. Boronizing being a thermochemical diffusion treatment can be applied to a wide range of steel alloys including carbon steel, low alloy steel, tool steel and stainless steel. Borides are non-oxide ceramics and could be very brittle. The aim of this study is to clarify the improvement of surface properties of AISI 316 L type stainless steel by thermo-chemical boronizing technique. In this study, boronizing bath was consisting of mixing of the silicon carbide, borax and boric acid in the salt bath. Boronizing process were performed different temperature and time. After the boronizing process, the various tests to determine the properties of boride layer were done. The results of this investigation can be summarized as follows, a) Thickness of boride layer on the surface of boronized AISI 316 L stainless steel increased as a parabolic with increasing temperature and time, b) The boride layers of boronized samples show continuity the surface. The surface structure of boride layer is more homogeneous and more density,c) The basic phase for the boride layer occurred with boronizing technique was Fe2B. The FeB did not occur, d)Activation energy of boride layer occurred with boronizing was 231.886 kJ/mol, e)The surface roughness values of boronized samples increased both the increasing additive ratio and increasing boronizing temperature. There is not affair to the effect on the roughness of the boronizing time and the type of the additives, The residual stress of boride layer increased with increasing temperature. [ABSTRACT FROM AUTHOR]

In this study, effects of cemented carbide coated with TiC+TiN, coated with TiC, uncoated and CBN on the machinability of AISI 410 martensitic stainless steel was investigated. In the experiments chip root morphology, cutting forces and surface roughness were determined. Experiments were done in the dry turning conditions. The cutting speed, feed rate and depth of cut were kept constant as, 60 m/min, 0.12 mm/rev and 1.2 mm respectively. Cemented carbide tool coated with TiC+TiN gave maximum cutting forces. Although CBN gave the minimum cutting forces, it was observed that it fractured in a shorter machining length. The optimum values of cutting force and surface roughness were obtained from cemented carbide coated with TiC. [ABSTRACT FROM AUTHOR]

Metal/Ceramic joining technologies play a very important role in various aspects of the electronics and hightemperature component industries. Diffusion bonding is an advantageous technique for producing that type of joint since high-temperature mechanical resistance and defect-free interfaces can thus be achieved. However, one of the shortcomings of diffusion bonding is the high temperature needed for the bonding operation, which causes the development of high thermal stresses across the interface and fast growth of often undesirable reaction products. Usually, the residual stresses that originate from the metal are minimized by the addition of interlayer, which must be ductile and suitably reactive to both metal and ceramic in order to efficiently relieve the abovementioned thermal stresses. This study presents the weldability of the conventional stainless steel and prepared porous ceramic by diffusion welding. Different wetting materials (Ag, Cu and Ag-Cu-Ti alloy) with a thickness of about 100 µm were used with loading of 0.2 and 2 MPa pressures under vacuum-argon atmosphere and the applied temperatures were between 850, 875, and 900 °C for 45 minutes. The microstructure of metal-ceramic interface was investigated by scanning electron microscope (SEM) with EDS attachment for chemical analysis. The pores of the ceramic were filled with the Ag or its eutectic alloy through the interface with a thickness at about 40-60 µm. The joining mechanism of the stainless steel to ceramic was discussed with respect to diffusion and infiltration. [ABSTRACT FROM AUTHOR]

Copyright of Teknoloji is the property of Engineering Science & Technology, an International Journal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Teknoloji is the property of Engineering Science & Technology, an International Journal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Teknoloji is the property of Engineering Science & Technology, an International Journal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Teknoloji is the property of Engineering Science & Technology, an International Journal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)