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Omer Faruk Erkendirci - One of the best experts on this subject based on the ideXlab platform.
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investigation of the quasi static penetration resistance behavior of carbon fiber reinforced laminate hdpe composites
Composites Part B-engineering, 2016Co-Authors: Omer Faruk ErkendirciAbstract:Abstract In this paper, a study on the quasi-static penetration resistance behaviour of unidirectional carbon fiber fabric/High Density Polyethylene (HDPE) composite with two different thicknesses which are laminated 4L and 12L (4 layers & 12 layers), i.e., HC = 3.1 mm and 9.3 mm, is presented using the quasi-static Punch shear test (QS-PST) methodology for the experiments. The penetration resistance is usually shown by a load–displacement graph, integral of which is the energy dissipated by the composite during penetration. The penetration energy varies with the Diameter of the support span which can be equal or higher than the Punch Diameter. During tests, a flat Punch of Diameter 7.6 mm with a range of support spans 8.89 mm–50.8 mm has been used and QS-PST experiments are carried out for varying support span to Punch Diameter ratios (i.e., SPR = 1.16, 1.33, 1.67, 2.00, 2.33, 2.67, etc.). Their damage mechanisms for different SPRs and thickness are documented. Stiffness, peak force, deflection, damage area, and energy dissipation results are presented in detailed form.
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quasi static penetration resistance behavior of glass fiber reinforced thermoplastic composites
Composites Part B-engineering, 2012Co-Authors: Omer Faruk Erkendirci, Bazle Z HaqueAbstract:Abstract Quasi-static penetration resistance of a composite structure represents the energy dissipating capacity of the structure under transverse loading without dynamic and rate effects. In this paper, a comparative study of the quasi-static penetration resistance behavior of S-2 Glass/SC-15, S-2 Glass/HDPE and E-Glass/HDPE composite systems with varying thicknesses, i.e., 1.4–8.4-mm, is presented using the Quasi-Static Punch Shear Test (QS-PST) methodology developed earlier. The penetration resistance behavior is usually presented by a series of force–displacement graphs at different support conditions, the integral of which is the energy dissipated by the composite during the quasi-static penetration at corresponding support conditions. The penetration energy varies with the Diameter of the support span which is usually higher than the Punch Diameter, and also with the thickness of the composite laminate. During QS-PST experiments, a flat Punch of Diameter 7.6-mm with a range of support spans 8.89–50.8-mm has been used to obtain varying support span to Punch Diameter ratios (i.e., SPR = D S / D P = 1.16, 1.33, 1.67, 2.00, 2.33, 2.67, etc.). In order to compare the penetration resistance behavior of three different material systems, the S-2 Glass/SC-15, S-2 Glass/HDPE and E-Glass/HDPE composites of identical layer counts are used and the S-2 Glass/SC15 composite system is considered as the baseline. Composite plate specimens are sectioned after the test and then dipped into an ink–alcohol solution to study the damage mechanisms at different SPRs. Non-linear penetration stiffness and an average penetration resistance force are defined to quantify the average penetration resistance of each material. S-2 Glass and E-Glass reinforced HDPE composite material showed lower stiffness, lower peak force, higher deflection, lower damage area, and lower energy dissipation as compared to the baseline. A detailed comparison of results is presented.
Frank Vollertsen - One of the best experts on this subject based on the ideXlab platform.
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influence of tool geometry variation on the Punch force in micro deep drawing
Key Engineering Materials, 2013Co-Authors: Gerrit Behrens, Frank VollertsenAbstract:Micro forming processes are very well suited for manufacturing of small metal parts in large quantities and micro deep drawing provides a great application potential for the manufacturing of parts with complex shapes. But size effects like changed tribology and material properties usually result in smaller process windows for micro forming operations. Process caused wear as well as large inaccuracy in manufacturing of micro forming tools is responsible for geometrical deviation of the tools from nominal size. Both influences can have essential impact on the process window size and process stability. A better understanding of the influence of tool geometry on process stability can help to improve and optimize process control in micro forming. In addition, a quantitative judgment of the impact of wear and manufacturing inaccuracy will be possible. Therefore, in this study, the impact of different tool geometries on the Punch force in micro deep drawing was investigated. Significantly varied tool geometries were Punch Diameter, drawing gap, Punch and drawing die radius and shape of the die edge. FEM simulations as well as experiments were used to determine tool geometry influence on the Punch force of a micro deep drawing process. Hereby, it was possible to classify each geometry variation regarding its impact on the Punch force and therefore on one important parameter of the process stability. Results show that the greatest impact on the Punch force was caused by modifications of the Punch Diameter and variation of the drawing gap. Changes in Punch or drawing die radii proved to be of minor importance.
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drawability of thin magnetron sputtered al zr foils in micro deep drawing
Transactions of Nonferrous Metals Society of China, 2012Co-Authors: Gerrit Behrens, Frank Vollertsen, Julien Kovac, Bernd Kohler, Heinzrolf StockAbstract:Abstract Deep drawing provides a great application potential for the manufacturing of parts with complex shapes, even when it is scaled to the micro range. Two different foils out of the Al–Zr alloy with a thickness of about 15 μm were manufactured using a magnetron-sputtering process by applying substrate temperatures of 310 K and 433 K, respectively. These foils were used as blank material in micro deep drawing with a Punch Diameter of 0.75 mm to investigate the formability. Even though the materials show small ultimate strains in tensile tests, deep drawing was carried out successfully. Limit drawing ratios of 1.8 and at least 1.7 were reached for the material produced with a substrate temperature of 310 K and 433 K, respectively. These are even better results than those realized with Al-Sc alloys in former investigations. Comparison with deep drawing results of pure aluminum produced by conventional rolling shows the same achievable limit drawing ratio. This illustrates the good suitability of magnetron sputtering as a foil manufacturing process for micro sheet forming operations.
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characteristic of wear behavior of micro deep drawing tools
INTERNATIONAL CONFERENCE ON ADVANCES IN MATERIALS AND PROCESSING TECHNOLOGIES (AMPT2010), 2011Co-Authors: Huferathvon S Luepke, C Von Kopylow, Frank VollertsenAbstract:In order to investigate the wear behavior of the tools in micro forming, micro deep drawing with a Punch Diameter of 1 mm was performed. The stainless steel (German standard 1.4301) with a thickness of 0.025 mm was used as blank material. The forming tools are made of tool steel (German standard 1.2379). The mineral oil HBO 947/11 was used as lubricant. Two different failures resulting from tool wear were observed in this investigation. The experimentally measured Punch forces show no relation between the change of the maximum Punch force and the wear of micro deep drawing tools. Furthermore, the surface of the micro deep drawing tools was investigated using a confocal microscope. It was found that the surface quality of the used die changes clearly with the number of experiments. Moreover, the EDX analysis shows clearly that elements from the blank material exist on the surface of the die. This indicates an adhesive wear in micro deep drawing.
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analysis of Punch velocity dependent process window in micro deep drawing
Production Engineering, 2010Co-Authors: Frank VollertsenAbstract:Micro forming is an appropriate technology to manufacture very small metal parts, in particular for bulk production, as they are required in many industrial products resulting from micro technology. Deep drawing provides a great application potential for the manufacturing of parts with complex shapes, even in very small dimensions. Concerning the so called size effects micro deep drawing is widely investigated. However, this process is carried out usually under laboratory conditions with a relatively low Punch velocity, for example 1 mm/s. At the same time, the light weight of the forming tools for micro deep drawing makes it possible to vary the Punch velocity in a relatively large range. Furthermore, raising the Punch velocity is very meaningful for mass production in industry. Thus micro deep drawing with the Punch Diameter of 1 mm was performed with different Punch velocities (1, 10 and 100 mm/s) in this work, whereby the process behaviour, especially the experimentally acquired process window changes with variation of Punch velocities. The analysis in this work shows that the velocity dependent friction coefficients are responsible for the difference in process windows under different Punch velocities.
Bazle Z Haque - One of the best experts on this subject based on the ideXlab platform.
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quasi static penetration resistance behavior of glass fiber reinforced thermoplastic composites
Composites Part B-engineering, 2012Co-Authors: Omer Faruk Erkendirci, Bazle Z HaqueAbstract:Abstract Quasi-static penetration resistance of a composite structure represents the energy dissipating capacity of the structure under transverse loading without dynamic and rate effects. In this paper, a comparative study of the quasi-static penetration resistance behavior of S-2 Glass/SC-15, S-2 Glass/HDPE and E-Glass/HDPE composite systems with varying thicknesses, i.e., 1.4–8.4-mm, is presented using the Quasi-Static Punch Shear Test (QS-PST) methodology developed earlier. The penetration resistance behavior is usually presented by a series of force–displacement graphs at different support conditions, the integral of which is the energy dissipated by the composite during the quasi-static penetration at corresponding support conditions. The penetration energy varies with the Diameter of the support span which is usually higher than the Punch Diameter, and also with the thickness of the composite laminate. During QS-PST experiments, a flat Punch of Diameter 7.6-mm with a range of support spans 8.89–50.8-mm has been used to obtain varying support span to Punch Diameter ratios (i.e., SPR = D S / D P = 1.16, 1.33, 1.67, 2.00, 2.33, 2.67, etc.). In order to compare the penetration resistance behavior of three different material systems, the S-2 Glass/SC-15, S-2 Glass/HDPE and E-Glass/HDPE composites of identical layer counts are used and the S-2 Glass/SC15 composite system is considered as the baseline. Composite plate specimens are sectioned after the test and then dipped into an ink–alcohol solution to study the damage mechanisms at different SPRs. Non-linear penetration stiffness and an average penetration resistance force are defined to quantify the average penetration resistance of each material. S-2 Glass and E-Glass reinforced HDPE composite material showed lower stiffness, lower peak force, higher deflection, lower damage area, and lower energy dissipation as compared to the baseline. A detailed comparison of results is presented.
Eyup Yeter - One of the best experts on this subject based on the ideXlab platform.
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hybridization effects on quasi static penetration resistance in fiber reinforced hybrid composite laminates
Composites Part B-engineering, 2016Co-Authors: Mehmet Bulut, Ahmet Erklig, Eyup YeterAbstract:Abstract Quasi static penetration tests (QSPT) were conducted on fiber reinforced hybrid composite laminates with a circular and cylindrical Punch. Woven Carbon, Kevlar and S-glass fibers were used as reinforcing fibers for production of hybrid and non-hybrid composite laminates. Punch shear test procedures were employed until the perforation and complete plugging shear out of the laminate. During QSPT experiments, a flat end Punch with Diameter of 12.7 mm has been used for two different support spans (25.4 and 63.5 mm) to obtain two different support span (D s ) to Punch Diameter (D p ) ratios (SPR = D s /D p = 2 and 5). After the experiments, the extent of compression-shear and tension-shear based failure modes were characterized at constant Punch displacements of 8 and 10 mm for SPR = 2 and 5, respectively. In addition to visualize of front and back side surfaces, composite samples were half sectioned at damage region to observe the amount of delamination and damage through the thickness of the laminate. It was found that hybridization effects were distinctly observed with dominated tension-shear damage mode at SPR = 5.
Mathias Liewald - One of the best experts on this subject based on the ideXlab platform.
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hydromechanical deep drawing of cups with stepped geometries
Journal of Materials Processing Technology, 2008Co-Authors: T Khandeparka, Mathias LiewaldAbstract:Abstract This paper deals with the hydromechanical deep drawing of metal cups with complex stepped geometries. Two materials, a low-carbon steel (DC04) and stainless steel (DIN 1.4301), have been researched. A die set with a maximum possible deep drawing ratio β 0,max = 3.0 for a Punch Diameter ∅ 100 mm has been designed and constructed. The die set is designed to withstand fluid counter pressures up to 200 MPa. Pressure control is achieved using a micro-metering pressure control valve. The process is initially simulated using the FEM solver LS-DYNA. Experiments have been conducted with two Punch geometries. The Punch geometries consist of cylindrical and conical wall segments. Complex positive and negative features are manufactured in the Punch bottom face. The ability of transferring complex features from the Punch onto the blank surface with high deep drawing ratios is investigated. Extended limiting deep drawing ratios of β 0,max = 3.0 for DC04 and β 0,max = 2.875 for DIN 1.4301 have been achieved.
