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Bu tez çalışması Batman Üniversitesi Bilimsel Araştırma Projeleri Birimi tarafından BTÜBAP-2022-YL-03 nolu proje ile desteklenmiştir., Yüzey modifikasyonu olarak ifade edilen Tungsten Inert Gas (TIG) ile kaplama yönteminde, arzu edilen bileşim ve oranlarda, yüzeyde ince bir tabaka oluşturmak için, esas malzemeye metalurjik olarak bağlanmış kaplama malzemesinin hızlı katılaştırılması işlemine dayanmaktadır. Gaz tungsten ark yöntemiyle yapılan kaplama teknolojisi yeni bir yöntem değildir. Fakat yapılan işlem bakımından, üretimin aynı şartlarda daha kalın bir tabaka elde etmenin ve istenilen bileşim ve oranlarda bir kaplama tabakası oluşturmanın çok daha kolay uygulanması ve ucuz olması bakımından benzer yöntemlere göre daha avantajlıdır. Bu tez çalışmasında, alt tabakası 1040 paslanmaz çelik yüzeyine farklı oranlarda grafit takviyeli TiC/Grafit tozu TIG kaynak yöntemi kullanılarak yüzey kaplama işlemi yapılmıştır. Kaplama işlemi sonrası numuneler kaplama kalınlıkları ve mikroyapı morfolojisi optik mikroskop ile incelenmiştir. Ayrıca numunelerin taramalı elektron mikroskobu (SEM), Enerji dağılımlı spektrometresi (EDS), X-Işını kırınımı (XRD) cihazları ile mikroyapı, elementel dağılım ve faz bileşenleri analiz edilmiştir. Ayrıca kaplama tabakasının mekanik özelliklerini belirlemek için mikrosertlik ve aşınma cihazları kullanılıp sertlik değerleri ölçülmüş olup aşınma sonuçları mikroyapı ile karakterize edilmiştir. SEM ve EDS analiz sonuçlarından daha düzgün ve homojen kaplamaların oluştuğu ve yoğun dendritik yapıların olduğu gözlenmiştir. Kaplama ve alt tabaka arasında iyi bir metalurjik bağın oluştuğu optik mikroyapı ve SEM sonuçlarından tespit edilmiştir. EDS sonuçlarından görüldüğü üzere kaplama tabakasından alt tabakaya doğru gidildikçe Ti, C elementinin azaldığı gözlemlenmiştir. C elementinin ise kaplama tabakası ile birlikte arayüzün alt kısımlarına doğru gidildikçe artışını devam ettirdiği bunun temel nedeni olarak da alt tabakada yer alan C elementinin yüzeye doğru çıkmasından kaynaklandığı düşünülmektedir.XRD analiz sonucunda tüm numunelerde baskın fazın TiC fazı ile birlikte Fe7C3, Fe3C, martenzit fazlarının olduğu, düşük pik değerlerinde α-Fe ve δ-Fe fazlarının da oluştuğu tespit edilmiştir. Optik mikroskop yardımı ile ölçülen kaplama kalınlıklarında ise 1144 j/mm enerji girdisine sahip N2 numunesinde kaplama kalınlığı 2270 μm iken, 899 j/mm enerji girdisine sahip N4 numunesinde ise 580 μm olarak ölçülmüştür. Elde edilen sonuçlar ile TIG yöntemi ile kaplama çalışmasında kaplama kalınlığında enerji girdisinin önemli bir faktör olduğu düşünülmektedir.Kaplama yüzeylerinden alınan mikrosertlik ölçüm sonuçları değerlendirildiğinde %5C takviyeli numunenin 857 HV0.1 değeri ile en yüksek ortalama mikrosertlik değerine sahip olduğu gözlemlenmiştir. En düşük sertlik değeri ise %1 C takviyeli numuneden ise 756 HV0.1 ortalama mikrosertlik değeri elde edilmiştir. Takviyesiz olarak ölçüm yapıldığında ise 715 HV0.1 ortalama mikrosertlik değeri elde edilmiştir. Sonuç olarak C miktarı arttıkça sertliğin de buna bağlı olarak arttığı gözlemlenmiştir. Yüksek değerlerin ana kaynağının ergime akabinde katılaşma sonrası kaplama bölgesinde oluşan karbür fazlarının etkisi olduğu düşünülmektedir. C ilavesiyle birlikte mikrosertliğin en yüksek %5 C kaplama numunesinden elde edilmiştir. Aşınma sonuçları değerlendirildiğinde C ilavesine bağlı olarak sürtünme katsayısının düştüğü ve aşınma direncinin arttığı belirlenmiştir. Elde edilen sonuçlara göre en düşük sürtünme katsayısının N6 nolu numunede 0,2 elde edilirken en düşük sürtünme katsayısının ise N1 nolu numunede 0,6 olarak ölçülmüştür. Bu sonuçlar ışığında aşınma ve milkrosertlik değeri düşük olan AISI 1040 çeliğinin TiC/C ile kaplanması sonucunda mikrosertlik değerlerinin yükseldiği ve aşınma direncinin arttığı tespit edilmiştir., In the TIG coating method, which is expressed as surface modification, it is based on the rapid solidification of the coating material metallurgically bonded to the base material in order to form a thin layer on the surface in desired composition and proportions. The coating technology made by the gas tungsten arc method is not a new method. However, in terms of the process, it is more advantageous than similar methods in that it is much esasier and cheaper to produce a thicker layer under the same conditions and to create a coating layer with the desired composition and proportions. In this thesis, surface coating was performed on the substrate of 1040 stainless steel substrate by using pure TiC and graphite reinforced TiC/Graphite powder TIG welding method at different ratios (1,2,3,4,5, wt%). After the coating process, the coating thicknesses and microstructure morphology of the samples were examined with an optical microscope (OM), scanning electron microscope (SEM), Energy dispersive spektrometry (EDS), X-Ray diffraction (XRD) devices and microstructure, elemental distribution and phase components. In addition, microhardness and wear devices were used to determine the mechanical properties of the coating layer and the hardness values were measured and the wear results were characterized by microstructure. From the SEM and EDS analysis results, it was observed that more uniform and homogeneous coatings were formed and dense dendritic structures were observed. It was determined from the optical microstructure and SEM results that a good metallurgical bond was formed between the coating and the substrate. As can be seen from the EDS results, it was observed that Ti, C elements decreased as one went from the coating layer to the lower layer. On the other hand, it is thought that the element C continues to increase towards the lower parts of the interface together with the coating layer, and the main reason for this is that the element C in the lower layer rises towards the surface. As a result of XRD analysis, it was determined that the dominant phase was Fe7C3, Fe3C and martensite phases along with the TiC phase in all samples, and α-Fe and δ-Fe phases were also formed at low peak values. In the coating thicknesses measured with the help of an optical microscope, the coating thickness was 2270 μm in the N2 sample with an energy input of 1144 j/mm, while it was measured as 580 μm in the N4 sample with an energy input of 899 j/mm. With the results obtained, it is thought that the energy input in the coating thickness is an important factor in the coating work with the TIG method. When the microhardness measurement results taken from the coating surfaces were evaluated, it was observed that the 5% C reinforced sample had the highest average microhardness value with 857 HV0.1. The lowest hardness value. The average microhardness value of 756 HV0.1 was obtained from the 1% C reinforced sample. When the measurement was made without reinforcement, an average microhardness value of 715 HV0.1 was obtained. As a result, it was observed that as the amount of C increased, the hardness increased accordingly. It is thought that the main source of the high values is the effect of carbide phases formed in the coating region after solidification after melting. With the addition of C, the highest microhardness was obtained from the 5% C coating sample. When the wear results were evaluated, it was determined that the friction coefficient decreased and the wear resistance increased depending on the addition of C. According to the results obtained, the lowest friction coefficient was found to be 0.2 in the N6 sample, while the lowest friction coefficient was 0.6 in the N1 sample. In the light of these results, it was determined that the microhardness values increased and the wear resistance increased as a result of coating AISI 1040 steel, which has low wear and microhardness values, with TiC/C.

The ball joint parts made of forged steel are quite important in the suspension system. The quality of production of ball joint parts is very important because of their role. Some basic defects can be found in the hole edge form. These defects affect the hole quality of ball joint parts. In this study, the effects of cryogenic processing on the wear of AISI D2 punches and the effects of punch wear on the hole edge geometry of hot forged AISI 1040 steel ball joint parts were investigated. The hole geometry changes are generally associated with punch wear and process parameters. For the purpose of investigation, piercing was carried out using an eccentric press with AISI D2 tool steel punches on 6.0 mm-thick ball joint pieces. The punches were traditionally heat treated. Some of the punches were cryogenic-treated at -145 degrees C in addition to the conventional heat treatment. Weight loss values were measured to assess the punch wear, and SEM and OM images were analysed. At the end of the industrial piercing process, it was found that the D2 tool steel punch wear decreased with cryogenic process applied and the size changes in the hole edge geometry of the punched 1040 hot forged steel parts turned out to be less marked. TUBITAK/TEYDEBTurkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [1505]; University-Industry Cooperation Research Program [5150012] This study was supported by TUBITAK/TEYDEB 1505 University-Industry Cooperation Research Program under the scope of Project Number 5150012. WOS:000580444900006 2-s2.0-85091945605

Buçalışmada; AISI 1040 çeliği, elektrik ark ve MIG ile kaynatılıp, numunelerüretilmiştir. Kaynaklı ve kaynaksız numuneler tam tavlama, normalizasyon,menevişleme ve gerilim giderme işlemlerine tabi tutulmuşlardır. İşleme tabitutulan ve herhangi bir ısıl işlem yapılmayan numunelere çekme, üç nokta eğme,çentik darbe ve sertlik testleri yapılmıştır. Numunelerin çekme şekildeğiştirmeleri kaynaksız parçaların, kaynaklı parçalara nazaran daha yüksekelde edilmiştir. Kaynaksız ve elektrik ark kaynağı yapılıp, gerilim gidermeişlemi görmüş numunelerin akma ve çekme dayanım değerleri birbirlerine yakınelde edilmiştir. Martenzitik yapının dışarıda sert, içeri gittikçe yumuşak biryapı haline geldiği görülmüştür. Ölçülen sertlik değerlerinin, kaynak dolgumetalinin ortasından başlayıp genelde dışarıya doğru bir artış gösterdiğigözlenmiştir., Inthis study, AISI 1040 welding samples were produced by arc welding and MIG. Thefull annealing, normalizing, tempering and stress relief annealing treatmentwas applied for as-received and welded samples. Made process and untreatedsamples tensile, three point bending, impact and hardness tests were conducted.Tensile strain of the welded parts is higher than in the welded parts. Theyield and tensile strength of the as-received and electric arc welded samplehas similar value after stress relief treatment. Hard martensitic structure onthe outside, inside is seen increasingly become a soft structure. Increasing inhardness was observed starting from the weld filler metal to outside.

WOS: 000443177400010 In this study, for the turning of AISI 1040 steel that has cylindrical shape and hardened up to 46 HRc, Taguchi L-16 experimental design was created according to the parameters of cutting speed, feed rate and cutting depth which consist from four levels. Formed in result of turning, the total surface roughness (Rt) were measured. Regression models have been built Taguchi analyzes were carried out utilizing by MINITAB 14 Program for measured values of Rt The closest results of the test results, generated for the Rt regression model, were obtained with 99.8% specify coefficients in order second degrees regression model Signal/Noise (S/N) ratios were determined in design of the Taguchi. In ANOVA analysis, it was obtained as an effect of the 95% confidence level on Rt values in order feed rate. cutting depth and cutting speed. The result of the regression model and Taguchi analysis was determined as feed rate to be the optimum parameter for Rt values.

WOS: 000443167300001 In this study, AISI 1040 welding samples were produced by arc welding and MIG. The full annealing, normalizing, tempering and stress relief annealing treatment was applied for as-received and welded samples. Made process and untreated samples tensile, three point bending, impact and hardness tests were conducted. Tensile strain of the welded parts is higher than in the welded parts. The yield and tensile strength of the as-received and electric arc welded sample has similar value after stress relief treatment. Hard martensitic structure on the outside, inside is seen increasingly become a soft structure. Increasing in hardness was observed starting from the weld filler metal to outside.

Boriding is a thermo-chemical surface hardening treatment applied to iron based materials. This treatment is performed by boron element diffusing into iron based materials at high temperatures. Wear resistance increases by forming ferro-boron phases on the material surface. In addition, a very hard layer forms on the material surface. As a result, the tribological properties of the material increase. In this study, 6 different mixtures are prepared with B4C and SiC powders. In these mixtures steels of AISI 1020 and AISI 1040 are borided with a stainless steel crucible at a temperature of 900°C for 3 h. Depending on the boriding mixtures, the thickness of the borides formed on the surface of borided AISI 1020 and AISI 1040 steels ranged from 14 to 71 μm and from 10 to 64 μm, respectively. It is observed that the layer thickness increases with increase in B4C% ratio. The wear rate of steels increased with decreasing SiC ratio. The average value of obtained microhardness for borides of AISI 1020 and AISI 1040 steels are 1776 and 1860 HV0.05, respectively (17) (PDF) Investigation of surface properties and wear resistance of borided steels with different B4C mixtures. Available from: https://www.researchgate.net/publication/286196539_Investigation_of_surface_properties_and_wear_resistance_of_borided_steels_with_different_B4C_mixtures [accessed Jan 12 2020].