Browsing by Subject "Tensile strength"
Now showing 1 - 20 of 31
Results Per Page
Sort Options
Item A dynamic uniaxial wide strip tensile testing of two geotextiles in isolation(Elsevier Sci Ltd, 1999) Güler E.; Biro M.S.T.Geotextiles must sustain static, and often dynamic loads, during the lifetime of the structure in which they are placed. A test apparatus is constructed to examine the tensile behaviour and performance of two different low strength nonwoven geotextiles under dynamic loading. The apparatus is designed as a vertical uniaxial dynamic tensile testing equipment for testing geotextiles in isolation. The nonwoven geotextiles examined both performed well under rigorous test conditions. Charts and tables showing the measurements taken during tests and the results of these observations are presented.; Geotextiles must sustain static, and often dynamic loads, during the lifetime of the structure in which they are placed. A test apparatus is constructed to examine the tensile behaviour and performance of two different low strength nonwoven geotextiles under dynamic loading. The apparatus is designed as a vertical uniaxial dynamic tensile testing equipment for testing geotextiles in isolation. The nonwoven geotextiles examined both performed well under rigorous test conditions. Charts and tables showing the measurements taken during tests and the results of these observations are presented.Item Artificial neural networks modeling of mechanical property and microstructure evolution in the Tempcore process(2002) Çetinel H.; Özyiǧit H.A.; Özsoyeller L.In this study, the microstructures and the mechanical properties of steel bars treated by the Tempcore process have been investigated. In the Tempcore process, AISI 1020 steel bars of various diameters were used. In bars, unlike the self-tempering temperature and the extent of elongation, an increase in the amount of martensite was observed, which caused a consequential increase in yield and tensile strength as a function of quenching duration. The amounts of martensite, bainite, pearlite and the values of elongation, self-tempering temperature, yield and tensile strength could be obtained by a new and fast method, by using artificial neural networks. A PASCAL computer program has been developed for this study. In the numerical method, bar diameters and quenching durations were chosen as variable parameters. The numerical results obtained via the neural networks were compared with the experimental results. It appears that the agreement is reasonably good. © 2002 Elsevier Science Ltd. All rights reserved.Item Mechanical properties of magnesia and magnesia-chromite refractory materials(Trans Tech Publications Ltd, 2004) Köksal N.S.; Toparli M.; Altun I.A.In this study, modulus of rupture, elastic modulus and fracture toughness values were investigated at elevated temperature for magnesia and magnesia-chromite content of chromite between 6% and 20%. Modulus of rupture and elastic modulus values were calculated by three point bending test at temperatures 400, 600, 800 and 1400°C. Modulus of rupture and Young's modulus values decreased when temperature and content of chromite increased. Modulus of rupture and Young's modulus values at room temperature were compared to the values at 400, 600, 800 and 1400°C. Young's modulus values decreased to about 40% and modulus of rupture values decreased to about 25% of the values at room temperature. The samples were notched as a/h = 0.3 by cutting tool of 0.2 mm thickness. Fracture toughness values were calculated at each temperature. Fracture toughness value at room temperature was compared to the values at 400, 600, 800 and 1400°C. It was seen that fracture toughness values had decreased by the increase at temperature.Item Use of recycled concrete aggregates in Hot-Mix Asphalt(American Concrete Institute, 2006) Topal A.; Öztürk A.U.; Baradan B.The rubble from construction is generally used in landfill or thrown to natural areas at the end of their service life. Because continuously increasing production of concrete consumption, recycling of concrete waste materials will provide environmental protection and economical benefits. In this study, effects of fine and coarse recycled concrete aggregates on Hot-Mix Asphalt (HMA) performance were investigated. In performed experiments, Marshall Mixtures were prepared by using recycled concrete aggregates in the proportion of 10%, 20%, and 30% by mixture weight for the replacement of limestone in suitable gradation. Six different bitumen ratios were added to each mixture, respectively. Void %, flow and stability values were examined on 54 specimens. Furthermore, indirect tensile strength experiments were examined on the specimens having optimum 4.5% bitumen content and 30% recycled concrete aggregates. The results indicate that waste concrete can be used in HMA as aggregate to obtain the required Marshall stability and indirect tensile strength of the mixtures. However, the void percent of the mixture are not desirable due to the dense gradation of aggregate. Hence, gradation change is needed to Marshall Design criteria. © 2006 American Concrete Institute. All rights reserved.Item Mechanical properties and thermal analysis of low-density polyethylene + polypropylene blends with dialkyl peroxide(2010) Şirin K.; Balcan M.Polypropylene + low density polyethylene (PP + LDPE) blends involving 0, 25, 50, 75 and 100wt% of PP with dialkyl peroxide (DAP) were prepared by melt blending in a single-screw extruder. The effects of adding dialkyl peroxide on mechanical and thermal properties of PP + LDPE blends have been studied. It was found that at lower concentrations of peroxide (e.g., 0-0.08wt% of dialkyl peroxide) LDPE component is cross-linked and Polypropylene (PP) is degraded in all compositions of PP + LDPE blends. Mechanical properties (Tensile strength at break, at yield and elongation at break),Melt flow index (MFI), hardness, Scanning Electron Microscope (SEM) and thermal analyses (DSC) of these blends were examined. Because of serious degradation or cross-linking the mechanical properties and the crystallinty (%) of those products were decreased as a result of increasing peroxide content. © 2009 John Wiley & Sons, Ltd.Item Estimation of compression strength of polypropylene fibre reinforced concrete using artificial neural networks(2013) Eredm R.T.; Kantar E.; Gücüyen E.; Anil O.In this study, Artificial Neural Networks (ANN) analysis is used to predict the compression strength of polypropylene fibre mixed concrete. Polypropylene fibre admixture increases the compression strength of concrete to a certain extent according to mix proportion. This proportion and homogenous distribution are important parameters on compression strength. Determination of compression strength of fibre mixed concrete is significant due to the veridicality of capacity calculations. Plenty of experiments shall be completed to state the compression strength of concrete which have different fibre admixture. In each case, it is known that performing the laboratory experiments is costly and time-consuming. Therefore, ANN analysis is used to predict the 7 and 28 days of compression strength values. For this purpose, 156 test specimens are produced that have 26 different types of fibre admixture. While the results of 120 specimens are used for training process, 36 of them are separated for test process in ANN analysis to determine the validity of experimental results. Finally, it is seen that ANN analysis predicts the compression strength of concrete successfully.Item Pulsed Nd: YAG laser shock processing effects on mechanical properties of 6061-T6 alloy(2014) Gencalp Irizalp S.; Saklakoglu N.; Akman E.; Demir A.The aim of this paper is to investigate effects of single and double shot Nd:YAG laser shock processing (LSP) on residual stress, micro-hardness and tensile properties of 6061-T6 aluminum alloy. The X-ray diffraction technique was used to measure surface residual stress in LSP-treated 6061-T6 samples. The magnitude and directional dependence of the surface residual stress after single shot and double shot LSP were investigated with the sin2 Ψ method. The results show that laser shock processing can significantly increase surface compressive residual stress. In addition, micro-hardness of the LSP-treated sample was measured using a Vickers diamond indenter depending on the depth. The tensile tests of the single shot and double shot LSP-treated and untreated samples were carried out by the Schimadzu tensile testing machine having a video extensometer. Experimental results show that the values of micro-hardness, tensile strength and uniform elongation increase by LSP. © 2013 Elsevier Ltd. All rights reserved.Item Determination of properties of Althaea officinalis L. (Marshmallow) fibres as a potential plant fibre in polymeric composite materials(2014) Sarikanat M.; Seki Y.; Sever K.; Durmuşkahya C.The mechanical, thermal, chemical, crystallographic and morphological properties of althaea fibres, extracted from Althaea officinalis L., was examined for the first time in this study. A. officinalis L. was obtained from Mordoǧan, Izmir (Turkey). After extraction process, lignin, cellulose and hemicellulose contents of althaea fibres were identified. Fourier transform infrared and X-ray photoelectron spectroscopy were utilized for surface functional groups of althaea fibres. By using X-ray diffraction analysis, CI value for althaea fibre is obtained to be 68%. The images of scanning electron microscopy were taken for observation of morphology of althaea fibres. The tensile modulus and tensile strength values of althaea fibre were obtained by single fibre tensile tests as 415.2 MPa and 65.4 GPa, respectively. Thermogravimetric analysis showed that thermal degradation of the fibre begins at approximately 220°C. Besides, by pulling out the althea fibre from the embedded high density polyethylene, interfacial shear strength value was determined to be 8.16 MPa. The results suggest that the althaea fibre can be used in composite applications as a natural reinforcement material. © 2013 Elsevier Ltd. All rights reserved.Item Prediction of Hybrid fibre-added concrete strength using artificial neural networks(Techno-Press, 2015) Demir A.Fibre-added concretes are frequently used in large site applications such as slab and airports as well as in bearing system elements or prefabricated elements. It is very difficult to determine the mechanical properties of the fibre-added concretes by experimental methods in situ. The purpose of this study is to develop an artificial neural network (ANN) model in order to predict the compressive and bending strengths of hybrid fibre-added and non-added concretes. The strengths have been predicted by means of the data that has been obtained from destructive (DT) and non-destructive tests (NDT) on the samples. NDTs are ultrasonic pulse velocity (UPV) and Rebound Hammer Tests (RH). 105 pieces of cylinder samples with a dimension of 150 × 300 mm, 105 pieces of bending samples with a dimension of 100×100×400 mm have been manufactured. The first set has been manufactured without fibre addition, the second set with the addition of %0.5 polypropylene and %0.5 steel fibre in terms of volume, and the third set with the addition of %0.5 polypropylene, %1 steel fibre. The water/cement (w/c) ratio of samples parametrically varies between 0.3-0.9. The experimentally measured compressive and bending strengths have been compared with predicted results by use of ANN method. Copyright © 2015 Techno-Press, Ltd.Item Evaluation of linden fibre as a potential reinforcement material for polymer composites(SAGE Publications Ltd, 2016) Seki Y.; Seki Y.; Sarikanat M.; Sever K.; Durmuşkahya C.; Bozacı E.The aim of this study is to characterize linden fibres as a novel cellulose-based fibre to be used as a reinforcement material in composites and to investigate the adhesion property to unsaturated polyester. Up to now, there is no report regarding the potential usability of linden fibre in composite applications. Linden fibres were extracted from the stem of a plant of Tilia rubra DC. subsp. caucasica (Rupr.) V.Engl. Characterization of linden fibres was studied by Fourier transform infrared, X-ray photoelectron spectroscopy, thermogravimetric analysis, X-ray diffraction analysis, tensile and pull-out tests. Morphological properties of the fibres were observed through scanning electron and optical microscopes. Initial degradation temperature of the linden fibre was reported to be 238℃. The tensile strength and the Young’s modulus of the linden fibres were calculated to be 675.4 ± 45.7 MPa and 61.0 ± 9.8 GPa, respectively. The interfacial shear strength of the linden fibre with unsaturated polyester matrix was computed as 26.15 ± 2.27 MPa via pullout test. This study offers an alternative and eco-friendly reinforcement material which may have usability potential in polymeric composites. © 2014, © The Author(s) 2014.Item High strength and high ductility behavior of 6061-T6 alloy after laser shock processing(Elsevier Ltd, 2016) Gencalp Irizalp S.; Saklakoglu N.The plastic deformation behavior of 6061-T6 alloy which was subjected to severe plastic deformation (SPD) at high strain rates during laser shock processing (LSP) was researched. In LSP-treated materials, the near surface microstructural change was examined by TEM and fracture surfaces after tensile testing were examined by SEM. An increase in strength of metallic materials brings about the decrease in ductility. In this study, the results showed that LSP-treated 6061-T6 alloy exhibited both high strength and high ductility. TEM observation showed that stacking fault (SF) ribbon enlarged, deformation twins formed and twin boundary increased in LSP-treated 6061-T6 alloy. This observation was an indication of stacking fault energy (SFE) decrease. Work hardening capability was recovered after LSP impacts. © 2015 Elsevier Ltd. All rights reserved.Item Preparation and mechanical characterization of chicken feather/PLA composites(John Wiley and Sons Inc., 2017) Baba B.O.; Özmen U.Green composites, a bio-based polymer matrix is reinforced by natural fibers, are special class of bio-composites. Interest about green composites is continuously growing because they are environment-friendly. This study describes the preparation and mechanical characterization of green composites using polylactic acid (PLA) matrix including chicken feather fiber (CFF) as reinforcement. Extrusion and an injection molding process were used to prepare CFF/PLA composites at a controlled temperature range. CFF/PLA composites with fiber mass content of 2%, 5%, and 10% were manufactured. The effects of fiber concentration and fiber length on mechanical properties of CFF/PLA composites have been studied. Mechanical properties of composites were investigated by tensile, compression, bending, hardness, and Izod impact testing. The results of experiments indicated that Young's modulus, compressive strength, flexural modulus, and hardness of the PLA reinforced CFF composites are higher but tensile strength, elongation at break, bending strength and impact strength of them are lower than pure PLA. The results indicate that these types of composites can be used for various applications. POLYM. COMPOS., 38:837–845, 2017. © 2015 Society of Plastics Engineers. © 2015 Society of Plastics EngineersItem Thermal and mechanical properties of LDPE by the effects of organic peroxides(John Wiley and Sons Ltd, 2017) Sirin K.; Cengel Ö.; Canli M.In this study, the effect of different organic peroxides on different types of low-density polyethylene (LDPE) was investigated. LDPE products like F2-21T, F5-21T, and I22-19T were mixed in different proportions with dialkyl peroxide, dibenzoyl peroxide, and dilauroyl peroxide. Melt flow rates, mechanical properties (tensile strength at yield, tensile strength at break, elongation at break, and stress-strain effect), thermal analysis (differential scanning calorimetric and thermogravimetric analysis), and scanning electron microscopy images of the prepared mixtures were examined. Cross-linking occurred in the structure of LDPE types having different molecular weight distribution by the addition of even small amounts of peroxide (e.g. 0–0.12 wt%). Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.Item Collapse mechanism estimation of a historical slender minaret(Techno-Press, 2017) Nohutcu H.; Hokelekli E.; Ercan E.; Demir A.; Altintas G.The aim of this study is to accurately estimate seismic damage and the collapse mechanism of the historical stone masonry minaret "Hafsa Sultan", which was built in 1522. Surveying measurements and material tests were conducted to obtain a 3D solid model and the mechanical properties of the components of the minaret. The initial Finite Element (FE) model is analyzed and numerical dynamic characteristics of the minaret are obtained. The Operational Modal Analysis (OMA) method is conducted to obtain the experimental dynamic characteristics of the minaret and the initial FE model is calibrated by using the experimental results. Then, linear time history (LTH) and nonlinear time history (NLTH) analyses are carried out on the calibrated FE model by using two different ground motions. Iron clamps which used as connection element between the stones of the minaret considerably increase the tensile strength of the masonry system. The Concrete Damage Plasticity (CDP) model is selected in the nonlinear analyses in ABAQUS. The analyses conducted indicate that the results of the linear analyses are not as realistic as the nonlinear analysis results when compared with existing damage. Copyright © 2017 Techno-Press, Ltd.Item Effect of Heat Input on the Microstructure, Strength and Corrosion Behavior of Sheets of Alloy AA6061 After Cold Metal Transfer Welding(Springer, 2019) Çömez N.; Durmuş H.The effect of the parameters of welding conducted by the method of cold metal transfer on the geometry of the welding pool, the ultimate tensile strength, and the corrosion rate of welded joints of sheets from aluminum alloy AA6061 is studied. The influence of the current, voltage, and heat input rate during welding on the properties of the welded joints is analyzed. The welding parameters providing maximum ultimate strength and high corrosion resistance of welded joints of alloy AA6061 are determined. © 2019, Springer Science+Business Media, LLC, part of Springer Nature.Item Mechanical Properties and Corrosion Behavior of AA5754-AA6061 Dissimilar Aluminum Alloys Welded by Cold Metal Transfer(Springer New York LLC, 2019) Çömez N.; Durmuş H.The trend of using lightweight materials in the automotive industry brings along the necessity of dissimilar welding of aluminum alloys such as AA5754 and AA6061. Hybrid structures in automobiles are subjected not only to mechanical forces but also corrosive effects of the environment. In this study, cold metal transfer welding, which is suitable for welding thin sheets and dissimilar materials, was applied to join AA5754 to AA6061. It was aimed to investigate the effect of weld heat input on mechanical properties and corrosion rate measured by the Tafel extrapolation method in 3.5 wt.% NaCl solution at room temperature. The tensile strength of AA5754-AA6061 joints tended to reduce with increasing heat input. Corrosion test results showed that the increased heat input decreased the corrosion resistance and caused intergranular corrosion besides pitting corrosion. © 2019, ASM International.Item Investigation of fused deposition modeling processing parameters of 3D PLA specimens by an experimental design methodology(Carl Hanser Verlag, 2019) Celebi A.The main objective of this study is to analyze the tensile strength of PLA parts manufactured through fused filament fabrication (FFF) using a commercially available 3D printer. This study is primarily focused on the effects of the tensile strength of specimens subjected to the influence of four factors; layer thickness, fill density, raster orientation and sample structure type. A 233' mixed-level factorial design approach was used, and the individual effects of the four main factors and their Interactions determined. This experimental design had been implemented for two different infills: rectilinear and honeycomb. Specimens were printed at raster orientation angles of 30 60 0 and 90 0 at a fill density of 50 % and 100 %. A layer thickness of 0.15 mm and 0.05 mm was chosen for printing the specimens. The samples were tested using a standard tensile testing machine with an extensometer to determine mechanical strength characteristics such as ultimate tensile strength, maximum force and maximum elongation. The data obtained was then analyzed using Minitab 13.20 software. The results showed that 30 ° raster orientation yields the highest mechanical properties at each individual layer when compared to 60 ° and 90 The fill density proves to be the most influential parameter on tensile strength, followed by the sample structure type. The results also found tensile strength to directly proporionate to layer thickness. By improving the material properties through the addition of layers as observed In the results, it will be possible to provide support for software developers, mechanical designers and engineers to reduce manufacturing rime, material use and costs. © 2019 Carl Hanser Verlag. All rights reserved.Item Cold metal transfer welding of AA6061 to AA7075: Mechanical properties and corrosion(American Society of Mechanical Engineers (ASME), 2019) Çömez N.; Durmus H.Cold metal transfer (CMT) welding provides many advantages for welding of dissimilar materials and thin sheets with its superior heat input control mechanism. In this study, AA6061 and AA7075 aluminum alloys were joined with CMT welding. The effect of welding parameters on hardness, tensile strength, and corrosion rate was investigated. The Tafel extrapolation method was carried out to determine the corrosion rates of AA6061 and AA7075 base metals and AA6061–AA7075 joints. Increasing heat input was found to be detrimental for both mechanical properties and corrosion resistance. The outcomes showed that CMT welding produces adequate joints of AA6061–AA7075 in terms of mechanical properties and corrosion resistance, favorably with welding parameters that provide low heat input. © 2019 by ASME.Item Corrosion behavior and mechanical properties of cold metal transfer welded dissimilar AA7075-AA5754 alloys; [不同种类 AA7075-AA5754 合金冷态金属转移焊的腐蚀行为和力学性能](Central South University of Technology, 2020) Çömez N.; Durmuş H.Cold metal transfer (CMT) welding is a brand-new arc welding technique which shows adequate results for welding of thin sheets and dissimilar materials. Corrosion behavior of dissimilar aluminum joints should be determined in terms of predicting the effect of welding process on the possible failures in their constructions caused by corrosive agents. The present study investigates the effect of heat input on mechanical properties and corrosion rate of AA5754-AA7075 joints welded by CMT using ER5356 filler wire. Pore formation was observed not only in the weld metal but also in the partially melted zone of AA7075 base metal due to the vaporization of zinc. Increased heat input caused over aging and zinc vaporization in AA7075 base metal, and grain coarsening in AA5754 base metal consequently decreased the tensile strength. The average tensile strength of AA7075-AA5754 joints varies between 235 and 240 MPa. The ductile fracture occurred at the AA5754 base metal side in all samples. Pitting was observed as the dominant corrosion mechanism. Corrosion resistance tended to increase with increasing heat input. Heat input values between 95 and 110 J/mm are recommended for the optimization of corrosion resistance and strength. © 2020, Central South University Press and Springer-Verlag GmbH Germany, part of Springer Nature.Item Revealing the Long-term Ageing Effect on the Mechanical Properties of Chicken Feather Fibre/Poly(lactic acid) Biocomposites(Korean Fiber Society, 2021) Akderya T.; Özmen U.; Baba B.O.Recently, bio-based polymer composites have been preferred instead of petroleum-based polymer composites due to increased sensitivity, awareness, and interest level in the fields of depletion of oil resources and environmental pollution. These eco-friendly materials, also called green composites, are reinforced with natural fibres and have superior properties such as biodegradability. In this paper, the effect of long-term ageing on mechanical properties of biocomposite material containing chicken feather fibre (CFF) as additive and poly(lactic acid) (PLA) as matrix is studied. The mechanical properties of pure PLA and CFF/PLA biocomposites, which are gradually increasing in mass concentrations of 2 %, 5 % and 10 %, have been investigated by tensile, compressive and hardness tests, and also the fracture surfaces were examined by SEM micrographs. The experimental results show that the long-term ageing effect causes the mechanical properties of pure PLA and CFF/PLA biocomposites to decrease. The lowest values of mechanical properties are found in the 5 % and 10 % CFF/PLA biocomposite materials that have the highest mass concentration of CFF. © 2021, The Korean Fiber Society for Fibers and Polymers and Springer.