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    Automatic and Rapid Measurement in Artificial Intelligence-Aided Microstructure Analysis: A Deep Learning Approach Applied to AlSi9 Alloys
    (Springer Heidelberg, 2025) Kalkan, Mahmut Furkan; Kalkan, Ibrahim Halil; Yilmaz, Necip Fazil; Dispinar, Derya; Kahruman, Cem; Yavuz, Abdulcabbar
    This study showcases a proof-of-concept of an artificial intelligence-driven analytical technique that facilitates the automated extraction of significant quantitative data from microstructural images. Semantic segmentation and classification were conducted on eutectic Si particles and dendritic architectures utilizing microscopic images of AlSi9 alloys with varying Sr ratios. Following segmentation, characteristics including area, aspect ratio, maximum Feret diameter, circularity and SDAS were assessed automatically, and the resulting values were compared with both literature and manual measurements. The samples were effectively categorized based on their alteration levels using a CNN-based classification algorithm. This technology provides significant temporal and financial benefits for microstructural investigation by executing the entire procedure autonomously and expeditiously. The minimal error rates and elevated accuracy findings demonstrate the usefulness and dependability of the devised method for automated microstructural analysis. This paper exemplifies the application of artificial intelligence-driven microstructural analysis techniques in materials science, addressing a significant gap in the literature.
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    Brass alloys improved with antimony additives for gamma-ray shielding applications
    (Pergamon-Elsevier Science Ltd, 2026) Levet, Aytac; Kaur, Parminder; Kahruman, Cem; Thakur, Sonika; Buyukyildiz, Mehmet
    In the present research, brass alloys (Cu-63, Zn-37) have been modified with antimony content ranging from 0 to 5 % to enhance their radiation resistance. Comprehensive analyses were conducted to evaluate the effects of antimony doping on both the microstructural and radiation attenuation characteristics of these alloys. Phase diagrams and microstructural analysis revealed dendritic structures and Sb accumulation at grain boundaries at higher concentrations. The crucial radiation shielding parameters, including mass attenuation coefficient (MAC), effective atomic number (Zeff), effective electron density (Neff), half-value layer (HVL), and mean free path (MFP), were investigated both experimentally and theoretically across photon energies ranging from 81 to 383.9 keV. Results show that increasing antimony content enhances radiation absorption, with the 5 % Sb alloy demonstrating the highest shielding effectiveness. The MAC of the A6 brass alloy containing 5 % Sb showed a 15.5 % increase relative to the standard A1 brass alloy at 81 keV. These findings suggest that antimony-doped brass alloys can serve as effective, non-toxic alternatives for radiation shielding in nuclear, medical, and industrial applications.
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    Change in the Oxide Structure of Al-12Si Melts in the Presence of Sr
    (2023) Kahruman, Cem; Alev, Ugur; Dispinar, Derya
    Bifilm defects are the surface entrained double oxide films that are introduced into melts during turbulence and disturbance to the surface of the melt. These defects lead to porosity formation if they are not cleaned from the melt. Thus, the characterisation of the dross that is formed on the surface of the melt becomes a key parameter. In this work, Sr containing Al12Si alloy was used. For the modification process, 100, 200 and 300 ppm Sr was added to the alloy. The oxidation tests were carried out in liquid state at 700, 750 and 800 °C for holding durations of 12, 24, 36 and 48 hours. The structure was characterised by optical microscopy, Scanning Electron Microscopy, X-Ray Diffraction and X-ray photoelectron spectroscopy techniques. It was found that after 12 hours of holding, spinel oxides were formed on the surface mainly SrO.Al2O3 and MgO.Al2O3.
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    Statistical Distribution of Si Phases at Different Sr Levels in AlSi9 Alloys
    (Springernature, 2024) Kalkan, Ibrahim Halil; Hizli, Ibrahim Goksel; Dizdar, Kerem Can; Kahruman, Cem; Dispinar, Derya
    Al-Si alloys are widely used in many automotive applications. Mechanical properties of this alloy group strongly depend on the size, shape, and distribution of silicon phase. Therefore, Sr is added to alloy to alter the needle-like shape to fibrous morphology in order to achieve higher fluidity, increase feedability, decreased porosity, and high mechanical properties. In this work, the effect of strontium modification on the AlSi(9 )casting alloy were studied in detail. From 0 to 600 ppm, strontium was added to AlSi9 casting alloy and microstructural changes were evaluated. Metallographic characterization carried out on each sample and size and distribution of Si phase was analyzed by image analysis tools. Texture and pore figures were analyzed by EBSD.