Browsing by Author "Duran, Semih"

Now showing 1 - 8 of 8

Application of Honeycomb Pattern to Ti2AlN Max Phase Films by Plasma Etching
(Springer Heidelberg, 2024) Duran, Semih; Cicek, Hikmet; Korkmaz, Ismail Hakki; Efeoglu, Ihsan
The honeycomb pattern possesses a distinctive hexagonal structure capable of seamless repetition on a flat surface, leaving no gaps. Moreover, all arm thicknesses and angles are equal to one another. This remarkable configuration is deemed biomimetic, with numerous examples found in nature. Notably, it exhibits remarkably low density and exceptional mechanical strength. MAX phase films have gathered significant attention due to their exceptional capacity to amalgamate the essential properties of both metals and ceramics. Additionally, they possess the unique ability to effectively mend surface cracks that may arise as a result of friction-wear, restoring the material to a certain degree of integrity. In this study, Ti2AlN MAX phase thin films were deposited on M2 steel substrates by a closed field unbalanced magnetron sputtering system (CFUBMS). 750 degrees C heat treatment was applied to obtain the produced films in crystalline form. In addition, plasma etching parameters suitable for the phase structure of the deposited film were determined. With the inductive coupling plasma etching (ICP) process, the honeycomb pattern was given to the Ti2AlN MAX phase films with a continuous and smooth geometry at a depth of 2 mu m. This study gives ideas for the development of multi-coating systems in which patterns of different geometries are included in a single layer.
The Effect of Different Annealing Temperatures on the Mechanical and Tribological Properties of the Ti2aln Max Phase Films
(Sage Publications Inc, 2024) Cakir, Muhammet; Cicek, Hikmet; Duran, Semih; Yilmaz, Ahmet Melik; Gulten, Gokhan; Efeoglu, Ihsan
Ti2AlN MAX phase films produced at different N-2 flow rates and different annealing temperatures were deposited on 52100 steel substrates using the closed-field unbalanced magnetron sputtering technique. N-2 flow rates were changed to 2, 3.5, and 5 sccm. Due to the increasing N-2 flow rate, film thickness decreased from 2 to 1.3 mu m. Then the produced films were subjected to annealing at temperatures of 700, 750, and 800 degrees C. After the film produced at a flow rate of 2 sccm was annealed at 750 degrees C, the presence of the Ti2AlN MAX phase was determined. The binding energies of Ti 2p, Al 2p, and N 1s determined in the XPS analysis confirmed the existence of the Ti2AlN film. The friction coefficient measured for Ti2AlN MAX phase films was calculated as 0.53, the hardness value as 22.8 GPa, the elastic modulus as 291.4 GPa, and the wear rate as 2.96 x 10(-4) mm(3)/(Nm).
Effect of Post-Annealing on Structural, Tribological, and Adhesion Properties of TiW/TiWSi Graded Composite Films
(Elsevier Sci Ltd, 2025) Inanc, Ahmet Sami; Yilmaz, Ahmet Melik; Duran, Semih; Gulten, Gokhan; Cicek, Hikmet
TiW/TiWSi/TiWSiN graded composite films were synthesized on AISI 52100 steel substrates by employing a radio frequency (RF)-powered magnetron sputtering technique. Following deposition, post-annealing was applied to the films at various temperatures. X-ray diffraction (XRD) analysis revealed that the films exhibited an amorphous structure prior to annealing. Upon heat treatment, the formation of TiN crystalline phases with various orientations and planes became dominant in the structure. The crystalline formations were identified and validated by means of X-ray photoelectron spectroscopy (XPS). The A-600 film exhibited the lowest values in both friction coefficient (0.13) and wear rate (2.16 x 10-6 mm3/(N & sdot;m)) among all samples. Given these results, the A-600 film demonstrated notable wear resistance and exhibited the best tribological performance among the tested samples. Furthermore, heat treatment was found to improve adhesion performance; however, it was evident that the treatment temperature must be carefully optimized. While only the A-600 film remained intact after the scratch test, the presence of microcracks and cohesive failures in the other films indicated a loss of structural integrity. This study revealed that Ti-W-Si-N-containing films can achieve enhanced hardness, tribological, and adhesion properties following an appropriate heat treatment.
Investigation of Hardness, Tribological and Adhesion Properties of TiAlNiVn HEA Films Heat Treated at Different Temperatures
(Elsevier Sci Ltd, 2024) Yilmaz, Ahmet Melik; Cicek, Hikmet; Duran, Semih; Gulten, Gokhan; Efeoglu, Ihsan
TiAlNiVN high entropy alloy (HEA) films were firstly produced in the literature using the magnetron sputtering system. These films were subjected to heat treatments at different temperatures between 750 degrees C and 900 degrees C. Strong TiN and VN crystal structures were observed in all the annealed films. The composition of each element constituting TiAlNiVN HEA films was within a concentration range of 5-35 %. The presence of TiAlNiVN HEA films was confirmed by X-ray photoelectron spectroscopy (XPS) analysis. D-850 film had the highest hardness of 25.7 GPa and exhibited the lowest wear rate at 2.45 x 10(-5) mm(3)/(N.m), attributable to its lowest surface roughness (0.22) and friction coefficient (0.44). Subsequent to the heat treatment, there was a substantial enhancement in the adhesion performance of the films, culminating in a high critical load value of 80 N. This study revealed that nitride-based TiAlNiVN HEA films could be enhanced in terms of hardness, tribological, and adhesion properties after heat treatment. Considering the adhesion performance, it is anticipated that the films we have produced will be a promising alternative to traditional nitride-based coatings in challenging and complex service conditions.
Production of Honeycomb-Patterned Hybrid Ti2AlN/TiNi Films and Examination of Mechanical, Tribological, Adhesion and Fatigue Properties
(Elsevier, 2025) Duran, Semih; Cicek, Hikmet
Honeycomb-patterned hybrid Ti2AlN/TiNi films were produced on M2 and Inconel 718 substrates using a magnetron sputtering system. These films were subjected to heat treatment at 750 degrees C. In the XRD patterns of annealed films, crystalline formations corresponding to the Ti2AlN MAX phase (honeycomb edge) and super elastic TiNi (honeycomb inner) films were achieved. Mechanical properties were separately determined for each film area due to the honeycomb-patterned hybrid Ti2AlN/TiNi films having two different film areas. The film deposited on Inconel 718 exhibited the highest hardness values, with 10.2 GPa for the TiNi film and 25.4 GPa for the Ti2AlN film. Considering the results of wear tests performed both at room temperature and at high temperature, it was detected that the friction coefficients and wear rates of the films decreased by at least 50 % at high temperatures. Upon examining the adhesion performance of the films, the critical load values for the films deposited on M2 and Inconel 718 were 21 N and 26 N, respectively. According to the multi-pass scratch test results, it was observed that the film deposited on M2 maintained its structural integrity under a load of 7 N and exhibited better fatigue performance. This study proved that multi-coating components with different geometric architectures can be produced in a single layer. It also showed that such hybrid coatings exhibit good performance in machine components operating under various service conditions.
Production of TiNi/Ti2AlN Multilayer Films with Different Numbers of Layers and Evolution of Tribological and Adhesion Properties
(Wiley-VCH Verlag GmbH, 2025) Duran, Semih; Cicek, Hikmet; Yilmaz, Ahmet Melik; Efeoglu, Ihsan
TiNi/Ti2AlN multilayer films are deposited on AISI M2 steel and Inconel 718 substrates using the magnetron sputtering technique. After heat treatment at 750 degrees C, TiNi and Ti2AlN MAX phase crystal structures are obtained in these films. The effects of different layer numbers on the structural, mechanical, tribological, adhesion, and fatigue properties of TiNi/Ti2AlN multilayer films are investigated. All films' thickness is measured to be approximate to 2 mu m. The 20 layers film deposited on Inconel 718 exhibited the best mechanical properties, with a hardness of 30.6 GPa and an elastic modulus of 407 GPa. A significant improvement in the tribological performance of the films is observed with an increasing number of layers. The lowest wear rate, calculated as 1.96 x 10(-5) (mm(3) (Nm)(-1)), is observed for the 20 layers film deposited on Inconel 718 at room temperature. At high temperatures, the friction coefficients of the 16 and 20 layers films deposited on Inconel 718 decreased to 0.25. In terms of adhesion properties, the 10 layers films deposited on AISI M2 steel demonstrated the best performance with a critical load value of 45 N. The results of the multipass scratch test clearly showed that the 20 layers film deposited on Inconel 718 exhibited the best fatigue behavior among all films.
Structural and Tribological Properties of TiSin Films with Different Si Content
(Elsevier Science Sa, 2023) Cicek, Hikmet; Acar, Yunus Emre; Duran, Semih; Yilmaz, Ahmet Melik; Cakir, Muhammet
TiSiN thin films were deposited on 52100 steel and Al2024 substrates by magnetron sputtering method using Ti and Si targets in Ar+N2 atmosphere. Power values of 40 W, 60 W, and 75 W were applied to the Si target, while the voltage was constant at 370 V for the Ti target. The Si atomic ratios within the film's structure were found to vary in accordance with the increasing Si target power. The impact of varying Si atomic ratios on the structural, mechanical, and tribological properties of the films was investigated. X-ray diffraction, scanning electron mi-croscopy, hardness and wear test methods were performed. As the Si ratio increased from 10 at. % to 20 at. %, the maximum hardness value was 6.06 GPa for 52100 steel and 4.33 GPa for Al2024. With increasing Si content, the film thickness increased from 1.63 mu m to 2.05 mu m. The lowest surface roughness of the produced films was 0.069 for 52100 steel and 0.308 for Al2024. The lowest wear rate of TiSiN film was calculated at 1.63 x 10-4 mm3/(N.m).
Tini Max Kompakt Kaplamaların Üretilmesi, Yapısal, Mekanik, Tribolojik ve Kendi Kendini Onarma Özelliklerinin Araştırılması
(2024) Duran, Semih; Çiçek, Hikmet
Bu çalışmanın amacı TiNi/MAX filmlerin bal peteği desenine sahip formlarda ve çok katmanlı yapılarda bir araya getirilerek yeni nesil kompakt koruyucu kaplamaların üretilmesidir. Bu çalışma kapsamında magnetron sıçratma yöntemi kullanılarak Ti2AlN MAX fazı filmleri üretilmiştir ve üzerine plazma aşındırma yöntemiyle bal peteği deseni kazandırılmıştır. Daha sonra petek iç kısımları TiNi filmler ile doldurularak tek katmanda ikili kaplama sistemi geliştirilmiştir. Bunun yanında Ti2AlN ve TiNi filmlerden oluşan çok katmanlı filmler de üretilmiştir. Üretilen bu filmlerin yapısal, mekanik, tribolojik, adezyon, yorulma ve kendi kendini iyileştirebilme özellikleri araştırılmıştır. Çok katmanlı filmlerde katman sayısının artışına bağlı olarak mekanik ve tribolojik özelliklerin arttığı görülmüştür. Bal peteği desenli filmler ise özellikle yüksek sıcaklık koşullarında üstün tribolojik performans sergilemiştir. Çok katmanlı filmlerde artan katman sayısı katmanlar arasındaki toplam ara yüzey gerilimini arttırdığından dolayı adezyon özelliklerini olumsuz yönde etkilemiştir. Bal peteği desenli filmlerde, R1-M2 filminin taban malzeme ile daha iyi bir arayüz oluşturduğu tespit edilmiştir. Filmlerin kendi kendini iyileştirebilmesi için en uygun sıcaklık değeri 800°C olarak belirlenmiştir. Çok katmanlı filmlerde katman kalınlıkları azaldıkça TiNi-MAX sistemi daha iyi bir uyum ortaya koymuş ve filmlerin iyileşme performansı artmıştır. Özellikle bal peteği desenine sahip R1-M2 filminin hasarlı bölgelerinde ısıl işlem sonrasında iyi derecede iyileşmeler görülmüş ve O, Ti ve Al elementlerinin tespit edilmesi, Ti2AlN filminin kendi kendini iyileştirebilme yeteneğine sahip olduğunu açıkça göstermiştir.