The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Nikhil Gupta - One of the best experts on this subject based on the ideXlab platform.
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determining elastic Modulus from dynamic mechanical analysis a general model based on Loss Modulus data
Materialia, 2018Co-Authors: Nikhil GuptaAbstract:Abstract Dynamic mechanical analysis (DMA) method is used to measure viscoelastic properties such as storage and Loss moduli of materials. The present work is focused on developing a generalized model that allows transforming the storage and Loss moduli obtained from DMA to time domain elastic Modulus values. The model is capable of transforming the Loss Modulus data that may have multiple transition peaks in the test temperature range into elastic Modulus over a wide range of temperatures and frequencies. In order to develop the model, the storage Modulus is divided into frequency dependent and independent components, which are analyzed separately to build a general transform for strain rate sensitive and insensitive material properties. To test the accuracy of the model, the model is validated with experimental data obtained on ethylene-vinyl acetate (EVA). The secant moduli obtained from tensile tests and Loss Modulus transform are compared and the average error is found to be 1.1% in the strain rate range of 10−6/s to 10−2/s, which provides validation for the model. The proposed method eliminates the need for conducting numerous tensile tests to obtain Modulus over various temperatures and strain rates and replaces them with a single DMA experiment.
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dynamic properties of alumina hollow particle filled aluminum alloy a356 matrix syntactic foams
Materials & Design, 2015Co-Authors: Luca Licitra, Dung D Luong, Oliver M Strbik, Nikhil GuptaAbstract:Abstract Dynamic properties of two aluminum alloy A356/alumina hollow particle syntactic foams that have densities of 1.61 and 2.11 g/cc are studied. The materials are characterized for quasi-static (10−3 s−1) and high strain rate (445–910 s−1) compression. The results show that the lower density syntactic foam has lower Modulus, compressive strength and plateau stress, but the lower density provides better specific properties than either the A356 alloy and higher density syntactic foam. The fracture mechanism of the syntactic foams was investigated by using high speed cameras. The particle failure is found to initiate the failure in the specimen, followed by shear failure of the matrix and particles. The A356 alloy and syntactic foams are also characterized for their dynamic mechanical properties to understand the effect of temperature and loading frequency on the storage and Loss moduli and damping parameter. The storage Modulus of A356 matrix and syntactic foams decreases but the Loss Modulus and damping parameter increase as the temperature increases. At the same temperature, the lower density material has lower storage Modulus and Loss Modulus. The storage Modulus of A356 alloy decreases steeply as the temperature is increased above 375 °C, whereas syntactic foams demonstrate better thermal stability.
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viscoelastic properties of hollow glass particle filled vinyl ester matrix syntactic foams effect of temperature and loading frequency
Journal of Materials Science, 2013Co-Authors: Vasanth Chakravarthy Shunmugasamy, Dinesh Pinisetty, Nikhil GuptaAbstract:Viscoelastic properties of hollow particle-reinforced composites called syntactic foams are studied using a dynamic mechanical analyzer. Glass hollow particles of three different wall thicknesses are incorporated in the volume fraction range of 0.3–0.6 in vinyl ester resin matrix to fabricate twelve compositions of syntactic foams. Storage Modulus, Loss Modulus, and glass transition temperature are measured and related to the microstructural parameters of syntactic foams. In the first step, a temperature sweep from −75 to 195 °C is applied at a fixed loading frequency of 1 Hz to obtain temperature dependent properties of syntactic foams. In the next step, selected four compositions of syntactic foams are studied for combined effect of temperature and loading frequency. A frequency sweep is applied in the range 1–100 Hz and the temperature is varied in the range 30–140 °C. Time–temperature superposition (TTS) principle is used to generate master curves for storage Modulus over a wide frequency range. The room temperature Loss Modulus and maximum damping parameter, Tanδ, are found to have a linear relationship with the syntactic foam density. Increasing volume fraction of particles helps in improving the retention of storage Modulus at high temperature in syntactic foams. Cole–Cole plot and William–Landel–Ferry equation are used to interpret the trends obtained from TTS. The correlations developed between the viscoelastic properties and material parameters help in tailoring the properties of syntactic foams as per requirements of an application.
Vasanth Chakravarthy Shunmugasamy - One of the best experts on this subject based on the ideXlab platform.
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viscoelastic properties of hollow glass particle filled vinyl ester matrix syntactic foams effect of temperature and loading frequency
Journal of Materials Science, 2013Co-Authors: Vasanth Chakravarthy Shunmugasamy, Dinesh Pinisetty, Nikhil GuptaAbstract:Viscoelastic properties of hollow particle-reinforced composites called syntactic foams are studied using a dynamic mechanical analyzer. Glass hollow particles of three different wall thicknesses are incorporated in the volume fraction range of 0.3–0.6 in vinyl ester resin matrix to fabricate twelve compositions of syntactic foams. Storage Modulus, Loss Modulus, and glass transition temperature are measured and related to the microstructural parameters of syntactic foams. In the first step, a temperature sweep from −75 to 195 °C is applied at a fixed loading frequency of 1 Hz to obtain temperature dependent properties of syntactic foams. In the next step, selected four compositions of syntactic foams are studied for combined effect of temperature and loading frequency. A frequency sweep is applied in the range 1–100 Hz and the temperature is varied in the range 30–140 °C. Time–temperature superposition (TTS) principle is used to generate master curves for storage Modulus over a wide frequency range. The room temperature Loss Modulus and maximum damping parameter, Tanδ, are found to have a linear relationship with the syntactic foam density. Increasing volume fraction of particles helps in improving the retention of storage Modulus at high temperature in syntactic foams. Cole–Cole plot and William–Landel–Ferry equation are used to interpret the trends obtained from TTS. The correlations developed between the viscoelastic properties and material parameters help in tailoring the properties of syntactic foams as per requirements of an application.
S M Sapuan - One of the best experts on this subject based on the ideXlab platform.
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thermal properties of treated sugar palm yarn glass fiber reinforced unsaturated polyester hybrid composites
Journal of materials research and technology, 2020Co-Authors: Mohd N Nurazzi, S M Sapuan, A Khalina, R A Ilyas, Ayu S Rafiqah, Z M HanafeeAbstract:Abstract In this work, the effects of alkaline treatment and hybridization on the thermal properties of sugar palm yarn/glass fiber were investigated. The sugar palm fiber was treated with 1% of sodium hydroxide (NaOH) solution for 1 h and the ratio of between matrix and reinforcement was 70/30 wt.% and 60/40 wt.%, respectively, while the ratio of reinforcement between sugar palm yarn fiber and glass fiber was 70/30 wt.%, 60/40 wt.% and 50/50 wt.%, respectively. The thermal properties of the hybrid composites were analyzed using a dynamic mechanical analyzer (DMA) and Thermogravimetric analysis (TGA). The storage Modulus (E'), Loss Modulus (E") and damping factor (tan δ) were evaluated as a function of the alkaline treatment and different percentages of fiber loading. Also, the peak high was investigated for the tan δ curves. In the glassy state area, a higher glass fiber loading hybridized with treated sugar palm fiber exhibited the highest storage Modulus, Loss Modulus and the lowest damping factor. TGA demonstrated that the percentage of residue decreased as the glass fiber loading increased. Overall, the hybridization of glass fiber with treated sugar palm fiber enhances the thermal properties of the hybrid composites for structural applications.
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thermal properties of sugar palm glass fiber reinforced thermoplastic polyurethane hybrid composites
Composite Structures, 2018Co-Authors: A Atiqah, Mohammad Jawaid, S M Sapuan, M R Ishak, Othman Y AlothmanAbstract:Abstract The aim of this work to investigate the effect of glass fiber (GF) on the thermal properties of sugar palm (SP)/thermoplastic polyurethane (TPU) hybrid composites. Sugar palm/glass fiber hybrid composites at the different weight fraction of 0/40, 10/30, 20/20 and 30/10 were prepared by using melt-mixing compounding followed by hot pressing machine. Thermal properties of hybrid composites carried out by using Dynamic mechanical analyzer (DMA) and thermo-gravimetric analyzer (TGA). The storage Modulus (E′), Loss Modulus (E″) and damping factor (tan δ) were evaluated as a function of different relative sugar palm/glass fiber weight fraction. Also, the peak height was investigated for tan δ curves. At higher glass fiber loading exhibited the highest storage and Loss Modulus while the lowest damping factor was observed for higher sugar palm fiber loading. Thermogravimetric analysis (TGA) demonstrated that the amount of residue decreased as the glass fiber loading decreased. Overall, the hybridization of glass fiber with sugar palm/TPU composites enhances the thermal properties of the hybrid composites for automotive applications .
Othman Y Alothman - One of the best experts on this subject based on the ideXlab platform.
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thermal properties of sugar palm glass fiber reinforced thermoplastic polyurethane hybrid composites
Composite Structures, 2018Co-Authors: A Atiqah, Mohammad Jawaid, S M Sapuan, M R Ishak, Othman Y AlothmanAbstract:Abstract The aim of this work to investigate the effect of glass fiber (GF) on the thermal properties of sugar palm (SP)/thermoplastic polyurethane (TPU) hybrid composites. Sugar palm/glass fiber hybrid composites at the different weight fraction of 0/40, 10/30, 20/20 and 30/10 were prepared by using melt-mixing compounding followed by hot pressing machine. Thermal properties of hybrid composites carried out by using Dynamic mechanical analyzer (DMA) and thermo-gravimetric analyzer (TGA). The storage Modulus (E′), Loss Modulus (E″) and damping factor (tan δ) were evaluated as a function of different relative sugar palm/glass fiber weight fraction. Also, the peak height was investigated for tan δ curves. At higher glass fiber loading exhibited the highest storage and Loss Modulus while the lowest damping factor was observed for higher sugar palm fiber loading. Thermogravimetric analysis (TGA) demonstrated that the amount of residue decreased as the glass fiber loading decreased. Overall, the hybridization of glass fiber with sugar palm/TPU composites enhances the thermal properties of the hybrid composites for automotive applications .
Z M Hanafee - One of the best experts on this subject based on the ideXlab platform.
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thermal properties of treated sugar palm yarn glass fiber reinforced unsaturated polyester hybrid composites
Journal of materials research and technology, 2020Co-Authors: Mohd N Nurazzi, S M Sapuan, A Khalina, R A Ilyas, Ayu S Rafiqah, Z M HanafeeAbstract:Abstract In this work, the effects of alkaline treatment and hybridization on the thermal properties of sugar palm yarn/glass fiber were investigated. The sugar palm fiber was treated with 1% of sodium hydroxide (NaOH) solution for 1 h and the ratio of between matrix and reinforcement was 70/30 wt.% and 60/40 wt.%, respectively, while the ratio of reinforcement between sugar palm yarn fiber and glass fiber was 70/30 wt.%, 60/40 wt.% and 50/50 wt.%, respectively. The thermal properties of the hybrid composites were analyzed using a dynamic mechanical analyzer (DMA) and Thermogravimetric analysis (TGA). The storage Modulus (E'), Loss Modulus (E") and damping factor (tan δ) were evaluated as a function of the alkaline treatment and different percentages of fiber loading. Also, the peak high was investigated for the tan δ curves. In the glassy state area, a higher glass fiber loading hybridized with treated sugar palm fiber exhibited the highest storage Modulus, Loss Modulus and the lowest damping factor. TGA demonstrated that the percentage of residue decreased as the glass fiber loading increased. Overall, the hybridization of glass fiber with treated sugar palm fiber enhances the thermal properties of the hybrid composites for structural applications.
