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Scopus İndeksli Yayınlar Koleksiyonu

Permanent URI for this collectionhttps://hdl.handle.net/20.500.12573/395

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Author: search.filters.author.Kesriklioglu, SinanPublication Index: search.filters.publicationIndex.WoS

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Now showing 1 - 5 of 5
  • Article
    Surface Integrity and Tool Wear in S2-GFRP Milling: Experimental and Statistical Evaluation of Cutting Parameters and DLC and TiAlN Tool Coatings
    (Springer London Ltd, 2026) Danisman, Sengul; Yilmaz, Cagatay; Ersoy, Emin; Kesriklioglu, Sinan
    In this study, the surface integrity of S2-glass fiber-reinforced polymer (S2-GFRP) composites during milling with carbide cutters was investigated using a two-phase experimental design, focusing on surface roughness (Ra), burr area, and tool wear (VB). In the first phase, using a Taguchi L9 design, the effects of coating type (uncoated, TiAlN, DLC), spindle speed (2000-6000 rpm), and feed rate (0,15-0,25 mm/rev) on Ra and burr area were evaluated. In this short machining range where tool wear was negligible, the optimal combination yielding the lowest Ra (approximate to 0.97 mu m) and the minimum burr area (approximate to 231 mm & sup2;) was determined to be 4000 rpm, 0,15 mm/rev, and the DLC-coated tool. Regarding the effect of tool material on Ra, the DLC-coated tool provided approximately 4 and 2 times better results than the uncoated and TiAlN-coated tools, respectively. In the second phase, experiments extended up to 130 passes with this optimal parameter set showed that Ra increased significantly with increasing VB, and the burr area exhibited threshold-like behavior. In particular, a sudden increase in Ra and the burr area was observed when the VB approximate to threshold of approximately 100 mu m was exceeded; partial regression analyses confirmed different burr-formation tendencies in the low- and high-wear regimes. The results reveal that DLC coating initially provides superior performance in S2-GFRP milling, but surface degradation accelerates after the critical VB threshold.
  • Article
    Experimental Comparative Analysis of Hole-Making Strategies and Cutting Parameters on Flexural Properties and Induced Delamination in S2 Glass and Basalt Fiber-Reinforced Polymers
    (John Wiley and Sons Inc, 2026) Eltahir, Sara Saeed Abdulrahman; Yilmaz, Cagatay; Kesriklioglu, Sinan
    Open holes are often required in the applications of fiber-reinforced polymers (FRP). However, machining them leads to fiber and matrix damage, reducing the overall quality of composites. The novelty of this study lies in investigating the influence of multiple hole machining strategies under varying feed rates and cutting speeds on the flexural strength, chord modulus and hole quality for S2-Glass (S2-GFRP) and basalt fiber-reinforced polymers (BFRP), followed by three-point bending tests and statistical analysis to determine the optimum machining parameters in terms of flexural properties, delamination, and time efficiency. Findings indicate that conventional milling yields an increase in the flexural strength and chord modulus by 22.2 MPa and 1.9 GPa, respectively, for S2 GFRP. While climb milling performs best for BFRP, enhancing flexural performance by 7.6 MPa and 0.4 GPa. Direct drilling at high feed rate and cutting speed shows the poorest performance. Hole machining at low feed rate using climb milling minimizes delamination at the entrance by 14.8% for S2 GFRP and by 2.7% for BFRP using conventional milling. At the exit, helical milling at a low feed rate suppresses delamination damage by 58.5% and 10.7% for S2 GFRP and BFRP. The most time-efficient method is direct drilling at a feed rate of 0.075 mm/rev and cutting speed of 75 m/min or climb milling with same feed rate, but 25 m/min cutting speed. Within the tested ranges, the optimized drilling setup significantly improved structural performance of S2-GFRP and GFRP, confirming the effectiveness of the proposed experimental-statistical framework.
  • Article
    Minimization of Thermal Stresses in Instrumented Cutting Tools with Embedded Thin Film Thermocouples
    (Korean Society of Mechanical Engineers, 2026-04) Kesriklioglu, Sinan; Sivesoglu, Abdurrahman
    This study investigates the optimization of multilayer coatings on cutting tools to minimize thermal stress and temperature differences between the tool-chip interface and embedded thermocouples. The novelty of this study lies in directly linking coating architecture to temperature measurement accuracy, revealing that coatings not only affect heat dissipation and stress development but may also distort the apparent temperature recorded by embedded sensors. The types and thickness ranges of thin film layers in instrumented cutting tools were determined, and multi-physics finite element simulations were then used to evaluate coating configurations under thermal loading, assessing both stress distribution and temperature variance in the multilayer coating system. The Taguchi method, coupled with desirability analysis, identified optimal coating parameters that simultaneously minimize thermal stresses and temperature disparities, which are critical for accurate temperature measurements and extending the lifespan of cutting inserts. This framework enables a controllable trade-off between mechanical reliability and thermal measurement fidelity. The results reveal significant interactions among coating configurations (settings) and between thermal and mechanical properties of the materials used, demonstrating that careful selection of layer materials and thicknesses optimizes stress and temperature responses yielding thermal stress of 1628 MPa (second lowest and only 0.4 % higher than the minimum) and temperature difference of 12.1 degrees C (third lowest and 55 % lower than average). These findings underscore the potential of precise coating design to enhance tool performance and longevity in high temperature machining applications.
  • Article
    Citation - WoS: 5
    Citation - Scopus: 6
    Ineffectiveness of Flood Cooling in Reducing Cutting Temperatures During Continuous Machining
    (Springer London Ltd, 2022-09-19) Kesriklioglu, Sinan
    Water-based metalworking fluids are applied in the form of a liquid jet to flood the entire cutting zone and increase the tool life. The objective of this study is to investigate the effectiveness of flood cooling in reducing the tool chip interface temperatures during continuous cutting. An instrumented smart cutting tool with a thin film temperature sensor was fabricated to accurately measure the real-time cutting temperatures from 1.3 mu m below the tool chip interface in orthogonal turning of AISI 4140 steel under dry and flood cooling conditions. The cutting process was simulated in Deform 2D with the Johnson-Cook material model to present the transient temperature distributions on the coated cutting insert. The heat flux into the cutting tool was also estimated analytically and then three-dimensional finite element heat transfer simulations were performed to determine the maximum convective heat transfer of the cutting fluid in steady state. The measurements with the embedded thermocouple showed that flood cooling with a water-based cutting fluid slightly lowers the tool chip interface temperature. Moreover, the chip color may not be a good characteristic indicator to evaluate the cutting temperature in machining of metals. It was also found that flood cooling becomes more effective at a distance of approximately 150 mu m from the cutting edge where the chip does not contact the rake face of the cutting tool.
  • Article
    Citation - WoS: 10
    Citation - Scopus: 10
    Experimental and Statistical Damage Analysis in Milling of S2-Glass Fiber/Epoxy and Basalt Fiber/Epoxy Composites
    (Wiley, 2024-07-30) Sayin, Ahmed Cagri; Danisman, Sengul; Ersoy, Emin; Yilmaz, Cagatay; Kesriklioglu, Sinan
    S2-glass fiber reinforced plastics (S2-GFRP) and basalt fiber reinforced plastics (BFRP) have emerged as crucial materials due to their exceptional mechanical properties, and milling of composite materials plays an important role in achieving desired properties. However, they have proven challenges due to relative inhomogeneity compared with metals, resulting unpredictability in quality of milling operations. The objective of this work is to investigate the effect of cutting parameters, tool geometry and tool surface materials on the surface quality of composites using burrs as a metric. S2-GFRP and BFRP composites were produced by the vacuum infusion method. Helical and straight flute end mills were manufactured from high-speed steel (HSS) and carbide rounds, and half of them were coated with titanium nitride using reactive magnetron sputtering technique. Taguchi L18 orthogonal array is used to determine the effect of tool material, tool angle, coating, cutting direction, spindle speed, and feed rate on the machining quality of S2-GFRPs and BFRPs with respect to burr formations. Milling experiments were conducted under dry conditions and then the burrs were imaged to calculate the total area and length. Statistical analysis was also performed to optimize the machining parameters and tool type for ensuring the structural integrity and performance of the final composite parts. The results showed that the selection of tool material has the most significant impact on the burr area and length of the machined surface. The novel image analysis allows to analyze the extent of the burr size with a desirable operation speed for industrial applications.