Yazar "Teke, Ibrahim T." seçeneğine göre listele
Listeleniyor 1 - 14 / 14
Sayfa Başına Sonuç
Sıralama seçenekleri
Öğe A New Hybrid Method, Density-Shape-Element Removal (D-S-ER), for the Optimization of Continuum Structures(Pleiades Publishing Inc, 2023) Teke, Ibrahim T.; Yilmaz, Yasin; Baykara, Celalettin; Ertas, Ahmet H.Mesoscale lattice structures can be used in the design of lightweight structures using additive manufacturing without significantly raising production costs. However, creating effective structures with intricate latticework is difficult. Therefore, this paper presents a new strategy for designing additively manufactured structures that can simultaneously optimize the continuum structures. A novel hybrid algorithm has been created by combining the density-based approach, shape optimization, and element removal method (D-S-ER) to achieve the desired purposes of higher strength and/or lightweight structures. Three distinct issues-the cantilever beam, the corbel structure, and the GE bracket-that were addressed by many scientists were taken into account and resolved using the method that has been developed. As seen from the tables presenting the results obtained, significant improvements in terms of strength as well as the weight of the structures can be obtained. Hence, the results of the study demonstrate the effectiveness of the proposed procedure.Öğe A Predictive Model for Fatigue Performance in Spot Welded and Bolted Joints(Springer, 2025) Teke, Ibrahim T.; Baykara, Celalettin; Akbulut, Mustafa; Ertas, Ahmet H.This study examines the fatigue behavior of spot-welded and bolted single-lap joints through an integrated framework combining experimental testing, finite element analysis (FEA), and regression modeling. The investigation focuses on how geometric parameters-such as plate width, length, thickness, and overlap length-affect fatigue life under variable loading conditions. Fatigue tests serve as the foundation for developing a predictive model for low-cycle fatigue, while FEA provides detailed insights into stress concentrations at critical regions like weld nuggets and bolt holes. Results show that bolted joints, particularly those using M4 fasteners, exhibit superior fatigue performance due to more uniform stress distribution and reduced localization. Submodel-based FEA confirms these findings, revealing that bolted configurations better disperse stresses compared to the high gradients observed near spot welds. This combined approach enhances fatigue life prediction accuracy and offers practical guidance for optimizing joint geometry in automotive, aerospace, and mechanical engineering applications.Öğe An Experimental Study on Nodular Iron Machined Surfaces Utilizing a Capable 2D Finite Element Model for Precise Surface Roughness Estimation(Mdpi, 2024) Teke, Ibrahim T.; Ertas, Ahmet H.Nodular iron plays a crucial role in various industries, especially in large-scale applications such as gearboxes. Ensuring that nodular iron remains free from oil leakage and that contact surfaces are properly aligned is essential, given its operational requirements. Achieving flat contact faces through precise machining is therefore of utmost importance. As surface roughness and flatness are closely linked, it is vital to investigate the machining process parameters involved. This study focuses on addressing surface quality issues with EN-GJS-600-3 cast iron by optimizing machining parameters. CMM measurements were utilized to analyze the relationship between surface roughness and flatness, with a surface profile used to assess flatness. Furthermore, a new 2D surface roughness estimation method (2D-SRET) was created and tested with experimental data in order to improve the precision of assessing the discrete flat surface machining procedure.Öğe Assessment of Fatigue Life Under Three-Point Bending: Comparing S-D-S-ER and D-S-ER Techniques(Elsevier B.V., 2025) Teke, Ibrahim T.; Ertas, Ahmet H.In this study, it has been presented a novel approach to enhancing structural fatigue performance through the development and comparison of two methodologies: The Sub-modeling-Density-Shape-Element Removal (S-D-S-ER) method and the traditional Density-Shape-Element Removal (D-S-ER) method. Using three-point bending fatigue tests, the S-D-S-ER method is shown to significantly improve fatigue life and overall structural integrity by integrating sub-modeling into the design process. This contrasts with the conventional D-S-ER method, which displayed standard mechanical behavior and a markedly shorter lifespan. Notably, the S-D-S-ER model exhibited mechanical behavior similar to viscous materials-a characteristic often observed in composites-while the D-S-ER method did not. These results highlight the potential of advanced numerical modeling, particularly the S-D-SER approach, to enhance fatigue resistance and durability. This advancement is particularly relevant for the design and optimization of 3D-printed components, which are becoming crucial in industrial and biomedical applications. The adoption of such innovative methods could lead to significantly more reliable, long-lasting designs, with profound implications for the future of structural engineering and additive manufacturing. © 2025 The Authors. Published by ELSEVIER B.V.Öğe Carrier skid design for multi-model vehicle bodies: experimental and numerical insights(Emerald Group Publishing Ltd, 2025) Baykara, Celalettin; Teke, Ibrahim T.; Ertas, Ahmet H.PurposeThis study aims to redesign and optimize production skids in an automobile factory's paint shop to enhance productivity and efficiency within a lean manufacturing framework. By accommodating all vehicle types on a single skid design, the research seeks to minimize production time, reduce costs and improve operational reliability through total productive maintenance (TPM). The solution is robust in terms of its scalability to multiple vehicle models, significant cost savings and marked improvements in operational performance. The study also explores the effects of skid design and pallet rigidity on manufacturing line performance, providing a robust solution to streamline the production process while addressing key challenges in automotive manufacturing.Design/methodology/approachThe study uses a comprehensive methodology, combining numerical analysis (finite element analysis, [FEA]) and experimental validation, to redesign production skids for accommodating multiple vehicle types. Annual production data was analyzed to identify commonalities among car bodies for skid optimization. Lean principles - particularly Kaizen and TPM - uniquely influenced the redesign by emphasizing waste elimination, continuous improvement and equipment reliability. After conceptual design, FEA was used to evaluate skid rigidity under gravity loads for different pallet configurations (flexible vs. rigid). Virtual positioning of car models on design-verified skids preceded the fabrication and implementation of skids on the production line. Maintenance strategies included replacing worn-out components to ensure seamless operations. Numerical validation assessed the impact of pallet rigidity on skid deformations, enhancing the reliability of the proposed designs in a real-world manufacturing environment.FindingsThe optimized skid design successfully accommodated all vehicle types, reducing the number of skids, production time and costs. Efficiency gains included a 44% reduction in downtime and a 47% decrease in production line stops. Numerical analysis confirmed the significance of pallet rigidity in minimizing skid deformations, validating the redesign approach. In addition, eliminating a low-production car model further streamlined the process. A cost-benefit discussion showed that phasing out this model freed up skid capacity and reduced operational complexity, resulting in net savings. The integration of lean manufacturing principles and TPM demonstrated significant improvements in operational efficiency, offering a scalable framework for enhancing productivity in automotive manufacturing.Originality/valueThis study presents a novel approach to optimizing production skids for lean automotive manufacturing. By integrating numerical analysis, experimental validation and maintenance strategies, the research offers an innovative solution to common industry challenges, such as accommodating diverse vehicle types and reducing operational inefficiencies. Unlike previous studies that focus on single-vehicle fixtures, this work addresses a multimodel skid solution under a TPM-maintained environment. The findings emphasize the importance of considering pallet rigidity in skid design and demonstrate the practical benefits of eliminating low-production models. These insights provide valuable guidance for manufacturers seeking to enhance production line reliability, reduce costs and maintain a competitive edge in the automotive industry.Öğe Design optimization of a well-known geometry for minimum weight utilizing the Density-Shape-Element Removal method (D-S-ER)(EDP Sciences, 2024) Teke, Ibrahim T.; Ertas, Ahmet H.The development of topology optimization (TO) methods gives designers new capabilities. A variety of TO techniques have recently been used in special circumstances to expand the capabilities of generalist techniques on particular niche issues. To achieve more flexible solutions and generalized procedures for most of the problems, hybrid methods are in trend. Hence, in this study, a different application of the Density-Shape-Element Removal method (D-S-ER) has been used to reduce maximum stress while also significantly reducing the weight of the structure, a lifting hook. A raw model was taken into consideration for the procedure. The study's findings show that the suggested strategy can be employed to provide quick and effective solutions by means of optimizing the balance between weight and strength. One of the findings depicts that combining different methods could give flexibility even in well-proven geometry optimization, which is the lifting hook in this study. © 2024 EDP Sciences. All rights reserved.Öğe Effects of the single-lap joint on fatigue strength of metals with different surface coatings: a numerical simulation(EDP Sciences, 2023) Baykara, Celalettin; Teke, Ibrahim T.; Ertas, Ahmet H.Due to their low cost and ease of use, adhesives are frequently used in the industry. Selecting adherents and adhesives is essential when thinking about a construction that uses them. A fatigue study is therefore required to determine the best adherents and adhesives. In this situation, a prediction model must be incorporated into the process. In this study, Single-lap joint (SLJ) was chosen. Specimens with uncoated, primed, and cataphoresis-treated surfaces on DC01 steel sheet surfaces have been taken into account. A numerical solution was produced to obtain the fatigue life of the structures. Results indicate that the produced approach can provide an accurate estimate of fatigue resistance of different bonding methods including adhesive joints with various coating and adhesive thicknesses combined with adhesive techniques. © The Authors, published by EDP Sciences. This is an open access article distributed under the terms of the Creative Commons Attribution License 4.0 (https://creativecommons.org/licenses/by/4.0/).Öğe Enhancing structural analysis efficiency: a comprehensive review and experimental validation of advanced submodeling techniques, introducing the submodeling-density-shape-element removal (S-D-S-ER) method(Emerald Group Publishing Ltd, 2024) Teke, Ibrahim T.; Ertas, Ahmet H.PurposeThe paper's goal is to examine and illustrate the useful uses of submodeling in finite element modeling for topology optimization and stress analysis. The goal of the study is to demonstrate how submodeling - more especially, a 1D approach - can reliably and effectively produce ideal solutions for challenging structural issues. The paper aims to demonstrate the usefulness of submodeling in obtaining converged solutions for stress analysis and optimized geometry for improved fatigue life by studying a cantilever beam case and using beam formulations. In order to guarantee the precision and dependability of the optimization process, the developed approach will also be validated through experimental testing, such as 3-point bending tests and 3D printing. Using 3D finite element models, the 1D submodeling approach is further validated in the final step, showing a strong correlation with experimental data for deflection calculations.Design/methodology/approachThe authors conducted a literature review to understand the existing research on submodeling and its practical applications in finite element modeling. They selected a cantilever beam case as a test subject to demonstrate stress analysis and topology optimization through submodeling. They developed a 1D submodeling approach to streamline the optimization process and ensure result validity. The authors utilized beam formulations to optimize and validate the outcomes of the submodeling approach. They 3D-printed the optimized models and subjected them to a 3-point bending test to confirm the accuracy of the developed approach. They employed 3D finite element models for submodeling to validate the 1D approach, focusing on specific finite elements for deflection calculations and analyzed the results to demonstrate a strong correlation between the theoretical models and experimental data, showcasing the effectiveness of the submodeling methodology in achieving optimal solutions efficiently and accurately.FindingsThe findings of the paper are as follows: 1. The use of submodeling, specifically a 1D submodeling approach, proved to be effective in achieving optimal solutions more efficiently and accurately in finite element modeling. 2. The study conducted on a cantilever beam case demonstrated successful stress analysis and topology optimization through submodeling, resulting in optimized geometry for enhanced fatigue life. 3. Beam formulations were utilized to optimize and validate the outcomes of the submodeling approach, leading to the successful 3D printing and testing of the optimized models through a 3-point bending test. 4. Experimental results confirmed the accuracy and validity of the developed submodeling approach in streamlining the optimization process. 5. The use of 3D finite element models for submodeling further validated the 1D approach, with specific finite elements showing a strong correlation with experimental data in deflection calculations. Overall, the findings highlight the effectiveness of submodeling techniques in achieving optimal solutions and validating results in finite element modeling, stress analysis and optimization processes.Originality/valueThe originality and value of the paper lie in its innovative approach to utilizing submodeling techniques in finite element modeling for structural analysis and optimization. By focusing on the reduction of finite element models and the creation of smaller, more manageable models through submodeling, the paper offers designers a more efficient and accurate way to achieve optimal solutions for complex problems. The study's use of a cantilever beam case to demonstrate stress analysis and topology optimization showcases the practical applications of submodeling in real-world scenarios. The development of a 1D submodeling approach, along with the utilization of beam formulations and 3D printing for experimental validation, adds a novel dimension to the research. Furthermore, the paper's integration of 1D and 3D submodeling techniques for deflection calculations and validation highlights the thoroughness and rigor of the study. The strong correlation between the finite element models and experimental data underscores the reliability and accuracy of the developed approach. Overall, the originality and value of this paper lie in its comprehensive exploration of submodeling techniques, its practical applications in structural analysis and optimization and its successful validation through experimental testing.Öğe Fatigue Resistance in Engineering Components: A Comprehensive Review on the Role of Geometry and Its Optimization(Tech Science Press, 2025) Teke, Ibrahim T.; Ertas, Ahmet H.Fatigue failure continues to be a significant challenge in designing structural and mechanical components subjected to repeated and complex loading. While earlier studies mainly examined material properties and how stress affects lifespan, this review offers the first comprehensive, multiscale comparison of strategies that optimize geometry to improve fatigue performance. This includes everything from microscopic features like the shape of graphite nodules to large-scale design elements such as fillets, notches, and overall structural layouts. We analyze and combine various methods, including topology and shape optimization, the ability of additive manufacturing to finetune internal geometries, and reliability-based design approaches. A key new contribution is our proposal of a standard way to evaluate geometry-focused fatigue design, allowing for consistent comparison and encouraging validation across different fields. Furthermore, we highlight important areas for future research, such as incorporating manufacturing flaws, using multiscale models, and integrating machine learning techniques. This work is the first to provide a broad geometric viewpoint in fatigue engineering, laying the groundwork for future design methods that are driven by data and centered on reliability.Öğe Fatigue Testing and Life Prediction of Tensile Shear Spot-Welded Joints: A Comprehensive Review with Regression Modeling(Springer, 2025) Teke, Ibrahim T.; Ertas, Ahmet H.This study investigates the fatigue behavior of spot-welded tensile shear (TS) joints, emphasizing the influence of geometric parameters on fatigue performance under variable cyclic loading. Experimental fatigue testing of TS specimens reveals distinct failure mechanisms dependent on applied load levels. At high loads, failure predominantly occurs through shear at the weld nugget, whereas lower loads lead to crack propagation into the surrounding base material. To quantitatively assess the role of geometric parameters-including plate width, length, thickness, and overlap distance-a regression-based predictive model was developed, utilizing Delta F-N curves. The results indicate that increased plate width and thickness enhance fatigue resistance up to critical stabilization thresholds, while variations in plate length exhibit a non-monotonic influence, initially reducing fatigue strength before reaching an equilibrium. Overlap length, however, demonstrates minimal impact on fatigue life. Furthermore, the regression model, originally formulated for single-lap joints, was successfully applied to TS specimens, demonstrating its robustness and predictive accuracy across different joint configurations. These findings underscore the critical role of geometric optimization in enhancing the fatigue resistance of spot-welded structures and provide a robust framework for predictive modeling across various fatigue regimes, ensuring reliability under diverse cyclic loading conditions.Öğe Hybrid Framework for Structural Analysis: Integrating Topology Optimization, Adjacent Element Temperature-Driven Pre-Stress, and Greedy Algorithms(Tech Science Press, 2025) Teke, Ibrahim T.; Ertas, Ahmet H.This study presents a novel hybrid topology optimization and mold design framework that integrates process fitting, runner system optimization, and structural analysis to significantly enhance the performance of injection-molded parts. At its core, the framework employs a greedy algorithm that generates runner systems based on adjacency and shortest path principles, leading to improvements in both mechanical strength and material efficiency. The design optimization is validated through a series of rigorous experimental tests, including three-point bending and torsion tests performed on key-socket frames, ensuring that the optimized designs meet practical performance requirements. A critical innovation of the framework is the development of the Adjacent Element Temperature-Driven Prestress Algorithm (AETDPA), which refines the prediction of mechanical failure and strength fitting. This algorithm has been shown to deliver mesh-independent accuracy, thereby enhancing the reliability of simulation results across various design iterations. The framework's adaptability is further demonstrated by its ability to adjust optimization methods based on the unique geometry of each part, thus accelerating the overall design process while ensuring structural integrity. In addition to its immediate applications in injection molding, the study explores the potential extension of this framework to metal additive manufacturing, opening new avenues for its use in advanced manufacturing technologies. Numerical simulations, including finite element analysis, support the experimental findings and confirm that the optimized designs provide a balanced combination of strength, durability, and efficiency. Furthermore, the integration challenges with existing injection molding practices are addressed, underscoring the framework's scalability and industrial relevance. Overall, this hybrid topology optimization framework offers a computationally efficient and robust solution for advanced manufacturing applications, promising significant improvements in design efficiency, cost-effectiveness, and product performance. Future work will focus on further enhancing algorithm robustness and exploring additional applications across diverse manufacturing processes.Öğe Microstructure and Surface Roughness Connection on Machined Ductile Iron: An Experimental Determination(EDP Sciences, 2024) Teke, Ibrahim T.; Oktay, Mehmet; Baykara, Celalettin; Ertas, Ahmet H.Ductile iron is useful for a variety of engineering challenges because of its ductility and high strength. Hence, it is an excellent option if machining is required. After milling operations, however, various surface characteristics could be created, and surface roughness could be assessed. On the other hand, machined surface roughness is constrained by production requirements. As a result, the association between surface roughness and machining parameters has been studied in the literature. Studies that focus on the relationship between surface roughness and microstructure in the context of material qualities are also available. In this study, an experimental investigation of a part made of EN-GJS-600-3 material took into account the significance of the interaction between microstructure and surface roughness. In addition to machining parameters, surface roughness, hardness (Brinell Hardness), and microstructure of machined surfaces are taken into consideration. The findings show that surfaces with pearlitic compositions are highly abrasive. Hardness rose along with an increase in the pearlitic phase. The number of spheres and surface roughness follow the same trend. © The Authors, published by EDP Sciences. This is an open access article distributed under the terms of the Creative Commons Attribution License 4.0 (https://creativecommons.org/licenses/by/4.0/).Öğe Pre-stress-integrated FEA for failure prediction in 3D-printed and injection-molded polymers(Emerald Group Publishing Ltd, 2025) Teke, Ibrahim T.; Ertas, Ahmet H.PurposeThis study aims to improve the accuracy of failure prediction in polymer parts produced by additive manufacturing (AM) and injection molding (IM) by integrating manufacturing-induced residual stresses into finite element analysis (FEA). The main challenge addressed is the modeling of complex residual stress fields caused by anisotropy and non-uniform cooling. Despite this complexity, the proposed method improves simulation reliability, reduces prediction errors and more accurately identifies failure locations under mechanical loads.Design/methodology/approachThe study introduces the Adjacent Element Temperature-Driven Pre-Stress Algorithm (AETDPA), which embeds residual stresses into FEA using a breadth-first search-based mapping of thermal history. This approach enhances stress distribution accuracy and supports better fatigue life and structural durability predictions for fused deposition modeling and injection molded parts.FindingsApplying AETDPA significantly improves the accuracy of failure and deformation predictions by accounting for residual stresses often ignored in conventional FEA. The algorithm effectively captures anisotropy, layer-wise thermal behavior and manufacturing defects such as thermal strain and weld lines. Experimental validation through tensile and bending tests on acrylonitrile butadiene styrene and polylactic acid parts confirms the robustness and predictive capability of the approach.Originality/valueAETDPA overcomes key limitations of standard FEA by embedding process-induced stress effects directly into simulations. This enables more realistic stress profiles and fatigue predictions, contributing to improved design reliability and process control in critical applications, including automotive, aerospace and biomedical fields.Öğe Topology optimization and fatigue analysis of a lifting hook(Elsevier B.V., 2021) Teke, Ibrahim T.; Akbulut, Mustafa; Ertaş, Ahmet HanifiIn this study, a lifting hook has been redesigned with topology optimization and fatigue analysis has been done. With a density-based method, volume minimization has been achieved. All processes have been realized with the help of finite element method implemented in a commercial software. A standard lifting hook model has been used in the process. After optimization, the standard lifting hook was remodeled with CAD software. Then the new model was analyzed. This process has been repeated for three different models. On the basis of the obtained results, the topology optimization undertaken within the scope of the study demonstrates that it is possible to redesign a lifting hook with reduced weight and at the same time to satisfy the required strength properties.
