Journal articles: 'Viscoelastic material properties'

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Mohammadpour, Mehrdad, Hassan Asadigandomani, Mehdi Aminizade, and Saeed Raeisi. "Physical Characteristics, Clinical Application, and Side Effects of Viscoelastics in Ophthalmology." Journal of Current Ophthalmology 35, no. 4 (2023): 313–19. http://dx.doi.org/10.4103/joco.joco_178_23.

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Abstract Purpose: To explain the physical properties of ophthalmic viscoelastic devices (OVDs), covering their structural units, optimal features, existing viscoelastic materials, clinical applications, and potential side effects. Methods: This is a narrative review on the OVDs. A literature review was conducted in PubMed, Google Scholar, and Scopus databases. Studies that investigated physical characteristics, clinical applications, OVD commercial products, and their complications were included. Results: We included 42 articles from 2010 and discussed physical characteristics, properties of a desirable OVD, structural units of common OVDs, OVD commercial products, clinical applications, and also complications of OVDs. Conclusions: Today, viscoelastics hold a distinct and crucial role in intraocular surgery due to their remarkable properties. These materials safeguard the endothelium and epithelium, uphold anterior chamber depth, manage intraocular bleeding, ease tissue handling, and aid intraocular lens placement. Currently, the American market features 12 prevalent viscoelastic types, including 7 sodium hyaluronate derivatives (Healon, Healon-Greater Viscosity, Healon-5, Amvisc, Amvisc Plus, Advanced Medical Optics Vitrax, and Provisc), 2 hydroxypropyl methylcellulose 2% derivatives (OcuCoat and Cellugel), and 3 combinations of sodium hyaluronate and chondroitin sulfate (Viscoat, DisCoVisc, and DuoVisc). Despite the introduction of new viscoelastic materials annually, no single material encompasses all desired properties. Surgeons must select and employ suitable viscoelastics based on surgical conditions and patient requirements. Advancements in material development and understanding of physical properties and clinical applications continue to refine viscoelastic selection.

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Qausar, Mohammad. "Attenuation properties of viscoelastic material." Pure and Applied Geophysics PAGEOPH 131, no. 4 (1989): 703–13. http://dx.doi.org/10.1007/bf00876269.

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Lin, Che-Yu, Yi-Cheng Chen, Chin Pok Pang, and Tung-Han Yang. "Measurement Accuracy of Ultrasound Viscoelastic Creep Imaging in Measuring the Viscoelastic Properties of Heterogeneous Materials." Advances in Technology Innovation 7, no. 4 (2022): 229–41. http://dx.doi.org/10.46604/aiti.2022.9592.

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Ultrasound viscoelastic creep imaging (UVCI) is a newly developed technology aiming to measure the viscoelastic properties of materials. The purpose of this study is to investigate the accuracy of UVCI in measuring the viscoelastic properties of heterogeneous materials that mimic pathological lesions and normal tissues. The finite element simulation is used to investigate the measurement accuracy of UVCI on three material models, including a homogeneous material, a single-inclusion phantom, and a three-layer structure. The measurement accuracy for a viscoelastic property is determined by the difference between the simulated measurement result of that viscoelastic property and its true value defined during the simulation process. The results show that UVCI in general cannot accurately measure the true values of the viscoelastic properties of a heterogeneous material, demonstrating the need to further improve the theories and technologies relevant to UVCI to improve its measurement accuracy on tissue-like heterogeneous materials.

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Sun, Na, Kuan Jun Zhu, Bin Liu, Sheng Chun Liu, and Liang Liu. "Application Study of Viscoelastic Damping Material for the Anti-Galloping of Overhead Transmission Lines." Advanced Materials Research 884-885 (January 2014): 269–72. http://dx.doi.org/10.4028/www.scientific.net/amr.884-885.269.

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Based on the galloping mechanism of transmission line, it is determined to use viscoelastic damping material and energy effects of TMD to suppress galloping. The dynamic mechanical properties of viscoelastic damping material is studied, with the operating environment of the transmission lines, high-and-low-temperature physics experiment is carried out, while the experimental study on mechanical properties is carried out with the developed viscoelastic damping elements. It is showed that the viscoelastic material meets the anti-galloping device performance requirements for materials, it has a good energy consumption effect, suitable for application to anti-galloping of transmission lines.

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Yakubovskiy, Yuriy E., Vasiliy I. Kolosov, Irina A. Donkova, and Sergey O. Kruglov. "Modeling Viscoelastic Properties of Aging Material." Tyumen State University Herald. Physical and Mathematical Modeling. Oil, Gas, Energy 4, no. 4 (2018): 181–90. http://dx.doi.org/10.21684/2411-7978-2018-4-4-181-190.

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GAMOTA, DANIEL R., and FRANK E. FILISKO. "LINEAR/NONLINEAR MECHANICAL PROPERTIES OF ELECTRORHEOLOGICAL MATERIALS." International Journal of Modern Physics B 06, no. 15n16 (1992): 2595–607. http://dx.doi.org/10.1142/s0217979292001316.

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The stress response of an electrorheological (ER) material is modified by the application of an electric field. Various studies have shown that the ER material can behave as a linear viscous, linear viscoelastic, nonlinear viscoelastic, plastic, or viscoelastic-plastic body. Furthermore, several different experimental techniques are conducted to observe the ER material's behavior as a function of strain, strain frequency, field strength, and ER material concentration. Small amplitude dynamic studies are used to observe the ER material's linear viscoelastic properties, while moderate and large amplitude studies are used to observe the material's fundamental nonlinear dynamic properties. Finally, constant shear rate experiments are performed to observe the apparent viscosity of the ER material during flow conditions.

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Blanchard, James P., and Nasr M. Ghoniem. "Relaxation of Thermal Stress Singularities in Bonded Viscoelastic Quarter Planes." Journal of Applied Mechanics 56, no. 4 (1989): 756–62. http://dx.doi.org/10.1115/1.3176169.

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Singular thermal stress fields in bonded viscoelastic quarter planes are studied with the use of the viscoelastic analogy. The order of the singularity is shown to depend on the material properties, indicating that it will vary with time in viscoelastic materials. This is studied in detail for Maxwell materials, and it is shown that the order of the singularity generally increases with time. This evolution of the singularity can, for certain combinations of material properties, lead to initial increases in the stress levels near the edge of the interface before relaxation occurs.

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Tabakci, Alican, and Erhan Ilhan Konukseven. "Mechanical Properties Identification of Viscoelastic/Hyperplastic Materials Using Haptic Device Based Experimental Setup." Key Engineering Materials 486 (July 2011): 115–18. http://dx.doi.org/10.4028/www.scientific.net/kem.486.115.

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Mechanical behavior simulation of viscoelastic materials is a difficult task. In order to obtain accurate simulations, material model should be well chosen and hyperelastic characteristics of the viscoelastic materials should also be incorporated in the model. Once the material model is selected the coefficients can be identified with the help of mechanical tests/experiments. The main goal of this study is to optimize material model’s coefficients by using the designed indenter test setup results and inverse finite element modeling. Indenter test setup was designed by using a haptic device, force sensor and data acquisition card to test the mechanical properties of the viscoelastic/hyperelastic materials. Inverse finite element modeling method is used in order to model the materials according to their material characteristics. The model obtained from the analysis was optimized by using the data obtained from indenter tests. The conformity of the chosen model and the tested materials is shown by inverse finite element modeling and the material model coefficients are proved to be identified correctly.

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Lee, Hyun, Y. Richard Kim, and Seung Lee. "Prediction of Asphalt Mix Fatigue Life with Viscoelastic Material Properties." Transportation Research Record: Journal of the Transportation Research Board 1832, no. 1 (2003): 139–47. http://dx.doi.org/10.3141/1832-17.

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A simplified fatigue model is presented that can predict the fatigue life of asphalt mixes using viscoelastic properties only. This fatigue model was originally developed with the elastic-viscoelastic correspondence principle and continuum damage mechanics and was reduced to a simple version that can predict fatigue life with viscoelastic properties only. On the basis of the experimental study conducted on 12 different types of asphalt mixes, it was observed that the fatigue behavior of asphalt mixes is affected by both the viscoelastic properties and the fatigue characteristics, but mostly by the viscoelastic properties. In addition, it was found that the coefficient of conventional strain-based fatigue models could be expressed in terms of viscoelastic material properties. In the verification study, the fatigue model was able to predict the fatigue life of various types of mixes at the same level of prediction accuracy without change in model coefficients. The fatigue model was also able to accurately predict the changes in the fatigue life of an asphalt mix due to the changes in the volumetric mix properties.

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Meisel, Nicholas Alexander, David A. Dillard, and Christopher B. Williams. "Impact of material concentration and distribution on composite parts manufactured via multi-material jetting." Rapid Prototyping Journal 24, no. 5 (2018): 872–79. http://dx.doi.org/10.1108/rpj-01-2017-0005.

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Purpose Material jetting approximates composite material properties through deposition of base materials in a dithered pattern. This microscale, voxel-based patterning leads to macroscale property changes, which must be understood to appropriately design for this additive manufacturing (AM) process. This paper aims to identify impacts on these composites’ viscoelastic properties due to changes in base material composition and distribution caused by incomplete dithering in small features. Design/methodology/approach Dynamic mechanical analysis (DMA) is used to measure viscoelastic properties of two base PolyJet materials and seven “digital materials”. This establishes the material design space enabled by voxel-by-voxel control. Specimens of decreasing width are tested to explore effects of feature width on dithering’s ability to approximate macroscale material properties; observed changes are correlated to multi-material distribution via an analysis of ingoing layers. Findings DMA shows storage and loss moduli of preset composites trending toward the iso-strain boundary as composition changes. An added iso-stress boundary defines the property space achievable with voxel-by-voxel control. Digital materials exhibit statistically significant changes in material properties when specimen width is under 2 mm. A quantified change in same-material droplet groupings in each composite’s voxel pattern shows that dithering requires a certain geometric size to accurately approximate macroscale properties. Originality/value This paper offers the first quantification of viscoelastic properties for digital materials with respect to material composition and identification of the composite design space enabled through voxel-by-voxel control. Additionally, it identifies a significant shift in material properties with respect to feature width due to dithering pattern changes. This establishes critical design for AM guidelines for engineers designing with digital materials.

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Lin, Che-Yu. "Ramp-Creep Ultrasound Viscoelastography for Measuring Viscoelastic Parameters of Materials." Materials 13, no. 16 (2020): 3593. http://dx.doi.org/10.3390/ma13163593.

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Several ultrasound-based methods have been developed to evaluate the viscoelastic properties of materials. The purpose of this study is to introduce a novel viscoelastography method based on ultrasound acoustic radiation force for measuring the parameters relevant to the viscoelastic properties of materials, named ramp-creep ultrasound viscoelastography (RC viscoelastography). RC viscoelastography uses two different ultrasound excitation modes to cause ramp and creep strain responses in the material. By combining and analyzing the information obtained from these two modes of excitation, the viscoelastic parameters of the material can be quantitatively evaluated. Finite element computer simulation demonstrated that RC viscoelastography can accurately evaluate the viscoelastic parameters of the material, including the relaxation and creep time constants as well as the ratio of viscous fluids to solids in the material, except for the region near the top surface of the material. The novelty of RC viscoelastography is that there is no need to know the magnitude of acoustic radiation force and induced stress in the material in order to evaluate the viscoelastic parameters. In the future, experiments are necessary to test the performance of RC viscoelastography in real biomaterials and biological tissues.

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Liu, Lin Chao, Lie Yu, and Huan Xin Yu. "Steady State Response of Compressible Fractional Derivative Viscoelastic Thick-Walled Cylinder." Applied Mechanics and Materials 166-169 (May 2012): 1510–13. http://dx.doi.org/10.4028/www.scientific.net/amm.166-169.1510.

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Many materials show viscoelastic properties under long term load, because of the complexity of viscoelastic problem, it is not enough for describing the characteristics of material and structure with classic viscoelastic model. The stress-strain constitutive relationship is described by fractional derivative viscoelastic model, the radial displacement and stress of thick-walled cylinder under internal pressure are obtained by using Fourier transform and the properties of fractional derivative, and we also investigated the steady state response of compressible fractional derivative viscoelastic thick-walled cylinder.

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Li, Xiong, LunLun Wan, Fuyan Lin, and Chang Liu. "Study on the Testing Method of Relaxation Modulus under Spherical Indenter Loading." Advances in Materials Science and Engineering 2022 (October 11, 2022): 1–10. http://dx.doi.org/10.1155/2022/7171680.

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Viscoelastic materials are widely used in various fields. In order to better use viscoelastic materials in various working conditions, it is necessary to master the material properties of viscoelastic materials. Relaxation modulus is a characterization method of viscoelastic material properties. In this paper, by analyzing that viscoelastic materials are time-domain related parameters, the load-time curves are obtained by using the spherical indentation instrument to carry out the ramp loading indentation test at different speeds. According to the law of ramp strain history loading, the data at different velocities are summarized and a method for judging the linear viscoelastic boundary of viscoelastic materials in spherical indentation tests is obtained. Aggregate the load-time data at different speeds to obtain a set of valid data for a longer period of time. A method of measuring the relaxation modulus using the ramp-constant strain history is proposed. Compared with the ramp loading test method, it is simple and easy to operate, and it can make up for the short time period of the measured data in the ramp loading test. The experiment verifies the feasibility of the method of ramp-constant strain history.

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Rouleau, Lucie, Boris Lossouarn, and Jean-François Deü. "Optimal viscoelastic properties for passive damping treatments." INTER-NOISE and NOISE-CON Congress and Conference Proceedings 268, no. 3 (2023): 5816–23. http://dx.doi.org/10.3397/in_2023_0831.

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In the context of noise and vibration control, constrained viscoelastic materials can be used to reduce structure-borne noise of vibrating structure. This passive damping treatment finds many applications due to its robustness and low cost. While several approaches are proposed in the literature to optimise the placement of constrained viscoelastic patches, few studies has been dedicated to the optimisation of the viscoelastic material's properties. The difficulty stems from their frequency-dependency. In this work, a fractional derivative model is used to describe the complex frequency-dependent viscoelastic properties. This study illustrates the effectiveness of using surrogate modeling to predict the damping performance of viscoelastic patches. A multi-model reduction method combined with a modal parameter identification method is used to build a surrogate model at a reasonable computational cost. Once trained, this metamodel is explored to optimise the parameters of the fractional derivative model, thus allowing the design optimisation of viscoelastic properties. This approach could be extended to optimise the material properties of viscoelastic foams in the low frequency range.

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Ban, Hoki, Soohyok Im, and Yong-Rak Kim. "Nonlinear viscoelastic approach to model damage-associated performance behavior of asphaltic mixture and pavement structure." Canadian Journal of Civil Engineering 40, no. 4 (2013): 313–23. http://dx.doi.org/10.1139/cjce-2012-0289.

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This paper presents an integrated experimental–numerical effort to more accurately model the damage characteristics of asphalt mixtures and pavement structures than conventional elastic and (or) linear viscoelastic approaches can. To this end, Schapery's nonlinear viscoelastic constitutive model was implemented into a finite element software via user defined subroutine (user material, or UMAT) to analyze an asphalt pavement subjected to heavy truck loads. Then, a series of creep and recovery tests were conducted at various stress levels and at different temperatures to obtain the stress-dependent and temperature-sensitive viscoelastic material properties of asphalt mixtures. With the viscoelastic material properties characterized and the UMAT code, a typical pavement structure subjected to repeated heavy truck loads was modeled with the consideration of the effect of material nonlinearity with a realistic tire loading configuration. Three-dimensional finite element simulations of the pavement structure present significant differences between the linear viscoelastic approach and the nonlinear viscoelastic modeling in the prediction of pavement performance with respect to rutting and fatigue cracking. The differences between the two approaches underline the importance of proper and more realistic characterization of pavement materials and should be addressed in the process of performance-based pavement design.

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S., P. Panchenko. "NUMERICAL SIMULATION OF VISCOELASTIC MATERIALS." Science and Transport Progress, no. 5(53) (November 24, 2014): 157–65. https://doi.org/10.15802/stp2014/30811.

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Purpose. The main goal of this paper is to develop the numerical model of viscoelastic material using finite element method (FEM). The model was applied to asphalt-aggregate mixtures. Additionally the obtained numerical results with use of different FEM software were compared with experimental data. Methodology. In order to perform the investigation, the numerical specimen was built within FEM software. Material of the specimen was assumed to be viscoelastic. Viscoelastic materials are characterized by a combination of elastic behavior, which stores energy during deformation, and viscous behavior, which dissipates energy during deformation. It was assumed that the behavior of the material corresponds to generalized Maxwell model. The model consists of a spring element in parallel with a number of spring and dashpot Maxwell elements. Generalized Maxwell model consisting of 5 elements was offered at . Mechanical properties of the material correspond to the properties of real asphaltic material. Findings. As the result of calculations the stress and strain state of the asphalt specimen were obtained. To compare mechanical characteristics of the model with experimental data the dynamic elastic modulus and phase angle values were calculated. Originality. Viscoelastic material model based on generalized Maxwell scheme was developed using ANSYS software. In order to compare the numerical model of the material with real asphalt-aggregate mix data, the values of dynamic modulus and phase angle were selected. Analyzing the results of calculations one can see good correspondence of numerical material model to experimental data. Moreover, the numerical data obtained with ANSYS and LS-DYNA software were compared. Practical value. It should be emphasized that FEM gives the possibility of determining stresses and strains for asphalt pavement non-elastic models what is of great importance using mechanistic design procedures.

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Boiko, Andrey V., Victor M. Kulik, Basel M. Seoudi, H. H. Chun, and Inwon Lee. "Measurement method of complex viscoelastic material properties." International Journal of Solids and Structures 47, no. 3-4 (2010): 374–82. http://dx.doi.org/10.1016/j.ijsolstr.2009.09.037.

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Hilton, H. H., J. Hsu, and J. S. Kirby. "Linear viscoelastic analysis with random material properties." Probabilistic Engineering Mechanics 6, no. 2 (1991): 57–69. http://dx.doi.org/10.1016/0266-8920(91)90018-y.

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Cheng, Xing Kai, Ke Chen, and Jiang Li Lin. "Inverse Estimation of Viscoelastic Material Properties Based on Particle Swarm Optimization and Neural Network." Advanced Materials Research 488-489 (March 2012): 124–28. http://dx.doi.org/10.4028/www.scientific.net/amr.488-489.124.

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The accuracy of inverse estimation for viscoelastic material properties is usually affected by two main factors: mechanical model and the initial value of iterations. In our research, a new method based on artificial neural network and modified particle swarm optimization (PSO) is developed to estimate viscoelastic material properties. The artificial neural network is established to model the behavior of viscoelastic materials which has solved the model-dependent problem; and chaos algorithm is also added to PSO algorithm to improve its local escaping ability which helps us solve the initial-value problem. Feasibility of this method is demonstrated by both data from theoretical formula and FEM simulation experiment.

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Barkanov, Evgeny, Andris Chate, Sandris Ručevskis, and Eduards Skukis. "Characterisation of Composite Material Properties by an Inverse Technique." Key Engineering Materials 345-346 (August 2007): 1319–22. http://dx.doi.org/10.4028/www.scientific.net/kem.345-346.1319.

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An inverse technique based on vibration tests to characterise isotropic, orthotropic and viscoelastic material properties of advanced composites is developed. An optimisation using the planning of experiments and response surface technique to minimise the error functional is applied to decrease considerably computational expenses. The inverse technique developed is tested on aluminium plates and applied to characterise orthotropic material properties of laminated composites and viscoelastic core material properties of sandwich composites.

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Esmaeeli, Roja, Haniph Aliniagerdroudbari, Seyed Reza Hashemi, Chiran JBR, and Siamak Farhad. "Designing a New Dynamic Mechanical Analysis (DMA) System for Testing Viscoelastic Materials at High Frequencies." Modelling and Simulation in Engineering 2019 (March 25, 2019): 1–9. http://dx.doi.org/10.1155/2019/7026267.

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The aim of this study is to design a new dynamic mechanical analysis (DMA) measurement system that can operate for shear tests at frequencies as high as 10 kHz with strain amplitudes sufficient for viscoelastic materials operating in high-frequency deformation applications, such as tire rubbers. The available DMA systems in market cannot effectively operate for accurate and direct measurement of viscoelastic material properties for applications dealing with high-frequency deformation of materials. Due to this, the available DMA systems are used for indirect measurements at low frequencies and low temperatures, followed by using time-temperature superposition principle to predict the properties at high frequencies. The goal of this study is to make the range of the test broad enough to eliminate the use of the time-temperature superposition principle in the determination of properties of viscoelastic materials. Direct measurement of viscoelastic material properties and increasing the accuracy of results are the main motivations to design a new DMA system. For this purpose, the state-of-the-art technologies to achieve high frequencies and strain amplitudes as well as instrumentation and control of the system are studied. The design process is presented in this paper.

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Pawlak, Zdzisław, and Dawid Zwoliński. "Damping parameters of a steel structure with a viscoelastic layer in the base node." MATEC Web of Conferences 285 (2019): 00015. http://dx.doi.org/10.1051/matecconf/201928500015.

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The aim of the article is to estimate the damping properties of a steel structural element equipped with a viscoelastic layer (VS) in the base node. The viscoelastic material has a good energy dissipation properties, has a relatively high strength, and its properties remain unchanged over the time. However, its damping properties may vary for different temperatures and excitation frequencies. In this work, the effect of frequency was examined, but the influence of temperature was omitted. For the selected viscoelastic material, laboratory tests were carried out to estimate its ability to dissipate energy in various load states. The viscoelastic material was then used as a washer in the joint connecting the steel element to the concrete base. The dynamic test and numerical analysis carried out for the structure with the viscoelastic layer allow estimation of some damping parameters for the considered system.

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Uluutku, Berkin, Enrique A. López-Guerra, and Santiago D. Solares. "A new method for obtaining model-free viscoelastic material properties from atomic force microscopy experiments using discrete integral transform techniques." Beilstein Journal of Nanotechnology 12 (September 23, 2021): 1063–77. http://dx.doi.org/10.3762/bjnano.12.79.

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Viscoelastic characterization of materials at the micro- and the nanoscale is commonly performed with the aid of force–distance relationships acquired using atomic force microscopy (AFM). The general strategy for existing methods is to fit the observed material behavior to specific viscoelastic models, such as generalized viscoelastic models or power-law rheology models, among others. Here we propose a new method to invert and obtain the viscoelastic properties of a material through the use of the Z-transform, without using a model. We present the rheological viscoelastic relations in their classical derivation and their z-domain correspondence. We illustrate the proposed technique on a model experiment involving a traditional ramp-shaped force–distance AFM curve, demonstrating good agreement between the viscoelastic characteristics extracted from the simulated experiment and the theoretical expectations. We also provide a path for calculating standard viscoelastic responses from the extracted material characteristics. The new technique based on the Z-transform is complementary to previous model-based viscoelastic analyses and can be advantageous with respect to Fourier techniques due to its generality. Additionally, it can handle the unbounded inputs traditionally used to acquire force–distance relationships in AFM, such as ramp functions, in which the cantilever position is displaced linearly with time for a finite period of time.

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Pascual-Francisco, Juan B., Orlando Susarrey-Huerta, Leonardo I. Farfan-Cabrera, and Rockali Flores-Hernández. "Creep Properties of a Viscoelastic 3D Printed Sierpinski Carpet-Based Fractal." Fractal and Fractional 7, no. 8 (2023): 568. http://dx.doi.org/10.3390/fractalfract7080568.

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In this paper, the phenomenon of creep compliance and the creep Poisson’s ratio of a 3D-printed Sierpinski carpet-based fractal and its bulk material (flexible resin Resione F69) was experimentally investigated, as well as the quantification of the change in the viscoelastic parameters of the material due to the fractal structure. The samples were manufactured via a vat photopolymerization method. The fractal structure of the samples was based on the Sierpinski carpet at the fourth iteration. In order to evaluate the response of both the fractal and the bulk material under the creep phenomenon, 1 h-duration tensile creep tests at three constant temperatures (20, 30 and 40 °C) and three constant stresses (0.1, 0.2 and 0.3 MPa) were conducted. A digital image correlation (DIC) technique was implemented for strain measurement in axial and transverse directions. From the results obtained, the linear viscoelastic behavior regime of the fractal and the bulk material was identified. The linear viscoelastic parameters of both fractal and bulk materials were then estimated by fitting the creep Burgers model to the experimental data to determine the effect of the fractal geometry on the viscoelastic properties of the samples. Overall, it was found that the reduction in stiffness induced by the fractal porosity caused a more viscous behavior of the material and a reduction in its creep Poisson’s ratio, which means an increase in the compliance of the material.

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Kang, Kai. "Mechanical properties of metal and polymeric viscoelastic materials and their applications." Journal of Physics: Conference Series 2152, no. 1 (2022): 012055. http://dx.doi.org/10.1088/1742-6596/2152/1/012055.

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Abstract Nowadays, With the wide application of metals and polymeric materials, how to describe the property of Viscoelastic material and how to apply them in engineering has become more and more critical. Due to the lack of insight into the mechanical properties of viscoelastic materials, many scholars have done a lot of experiments in studying the behavior of viscoelastic materials. Axial tensile tests were conducted on specimens to derive different mechanical behaviors of metals, polymers, and other materials at different temperatures and loading rates. Metal can generally be divided into elastic and plastic parts, while polymeric materials have the phases of the linear elastic region, drawing region, and oriented molecular strength region. This paper also shows a test conducted by Argon, Ali S., and M. I. Bessonov of four different kinds of polymers at different circumstances of temperature. After that, the paper shows the application of viscoelastic materials as CLD in damping and some engineering problems caused by the mechanical properties of viscoelastic materials. Currently, research on viscoelasticity should mainly focus on the application of Finite Element Methods and the acquisition of more experimental data to establish a complete theoretical system.

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Jingwei, Zhang, Li Jia, Huang Chuhao, and Chen Shuo. "Study on dynamic viscoelastic constitutive model of nonwater reacted polyurethane grouting materials based on DMA." REVIEWS ON ADVANCED MATERIALS SCIENCE 61, no. 1 (2022): 238–49. http://dx.doi.org/10.1515/rams-2022-0004.

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Abstract Nonwater reacted polyurethane grouting materials are new materials developed to make up for the shortcomings of water-reactive materials in emergency rescue. However, its viscoelastic properties and constitutive model under dynamic loads have not been systematically studied. Based on dynamic thermal mechanical analysis (DMA), the dynamic viscoelastic indexes such as storage modulus, loss modulus, and loss factor of nonwater reacted polymer grouting material were obtained, and the frequency spectrum of polymer with different densities were analyzed. In addition, comparing and analyzing the classical viscoelastic constitutive models such as Maxewell model, Kelvin model, and Fractional model, the fourth-order generalized Maxwell model (GMM) was selected to construct the viscoelastic constitutive model of polyurethane grounding materials. Then, the parameters of the viscoelastic constitutive model of polyurethane grounding materials were obtained by using multi-objective shared parameter fitting method, and dynamic viscoelastic constitutive model of nonwater reacted polyurethane grouting materials was established. Furthermore, the viscoelastic constitutive model with different densities was verified by the DMA test. The results show that the dynamic viscoelastic constitutive model of nonwater reacted polyurethane grouting materials in the article can accurately and efficiently describe the dynamic viscoelastic properties of polyurethane grounding materials, which lays a foundation for the dynamic response analysis of polymer structures.

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Węgrzyk, Grzegorz, Dominik Grzęda, Milena Leszczyńska, et al. "Viscoelastic Polyurethane Foam Biocomposites with Enhanced Flame Retardancy." Polymers 16, no. 22 (2024): 3189. http://dx.doi.org/10.3390/polym16223189.

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The growing demand for viscoelastic polyurethane foams creates a need for new sustainable raw materials that support cost-effective production while maintaining the desired material performance and fire safety standards. In this regard, our study aimed to develop viscoelastic polyurethane foam composites with reduced flammability and a high proportion of renewable raw materials. To achieve this, blackcurrant pomace, expandable graphite and a third-generation blowing agent were introduced to a viscoelastic polyurethane foam composition containing a reactive flame retardant in the formulation. The effects of the incorporated additives on the foaming process, flammability, chemical structure, cellular structure, thermal properties and physico-mechanical properties of the composites were determined. The results showed that the viscoelastic foam composite containing 30 php of blackcurrant pomace and 15 php of expandable graphite had a pHRRmax 52% lower than that of the reference material. The additional use of a blowing agent enhanced the flame-retardant effect of the materials, resulting in a 67% reduction in pHRRmax of the composite compared to the reference material. Moreover, the developed biocomposites exhibited promising limiting oxygen index values of 26–28%, compared to the 21% shown for the reference sample. Consequently, the best-performing biocomposites achieved the V-0 flammability rating according to the UL-94 standard. This study’s results indicate the composites’ high application potential due to their reduced flammability and the materials’ desirable physical and mechanical properties.

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Wang, Yong Cheng. "Research on the Dynamic Characteristics of a Sphere Material." Applied Mechanics and Materials 246-247 (December 2012): 482–86. http://dx.doi.org/10.4028/www.scientific.net/amm.246-247.482.

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In this paper, we make a research on the dynamic characteristics of a sphere material, mainly using golf as an example. Golf is composed of such as poly butadiene rubber or other synthetic rubber, ion resin, etc. and different viscoelastic materials. The viscoelastic characteristics of this material are selected as spectrometer for evaluation. However, the impact performance of the golf course materials cannot pass such a test to assess, because golf have great impact on the deformation and high strain rate viscoelastic spectrometer. On the other hand, the impact properties of the metal can be used to assess the split Hopkinson pressure bar. However, the rod is not suitable to be used to evaluate the strain wave interference and noise propagation in the impact properties of the polymer materials. Therefore, the split Hopkinson pressure bar has been modified to make it more applicable to the valuation of the polymer materials. The article is based on the concept of modified split Hopkinson pressure bar to make the golf impact evaluation of the performance materials.

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Mahross, Hamada Zaki, and Kusai Baroudi. "Effect of silver nanoparticles incorporation on viscoelastic properties of acrylic resin denture base material." European Journal of Dentistry 09, no. 02 (2015): 207–12. http://dx.doi.org/10.4103/1305-7456.156821.

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ABSTRACT Objective: The objective was to investigate the effect of silver nanoparticles (AgNPs) incorporation on viscoelastic properties of acrylic resin denture base material. Materials and Methods: A total of 20 specimens (60 × 10 × 2 mm) of heat cured acrylic resin were constructed and divided into four groups (five for each), according to the concentration of AgNPs (1%, 2%, and 5% vol.) which incorporated into the liquid of acrylic resin material and one group without additives (control group). The dynamic viscoelastic test for the test specimens was performed using the computerized material testing system. The resulting deflection curves were analyzed by material testing software NEXYGEN MT. Results: The 5% nanoparticles of silver (NAg) had significantly highest mean storage modulus E’ and loss tangent Tan δ values followed by 2% NAg (P < 0.05). For 1% nanosilver incorporation (group B), there were no statistically significant differences in storage modulus E’, lost modulus E” or loss tangent Tan δ with other groups (P > 0.05). Conclusion: The AgNPs incorporation within the acrylic denture base material can improve its viscoelastic properties.

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Rudolphi, Thomas J., and Allen V. Reicks. "Viscoelastic Indentation and Resistance to Motion of Conveyor Belts Using a Generalized Maxwell Model of the Backing Material." Rubber Chemistry and Technology 79, no. 2 (2006): 307–19. http://dx.doi.org/10.5254/1.3547939.

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Abstract A one-dimensional Winkler foundation and a generalized viscoelastic Maxwell solid model of the belt backing material are used to determine the resistance to motion of a conveyor belt over idlers. The viscoelastic material model is a generalization of the three-parameter Maxwell model that has previously been used to predict the effective frictional coefficient of the rolling motion. Frequency, or loading rate, and temperature dependence of the material properties are incorporated with the time/temperature correspondence principle of linear viscoelastic materials. As a consequence of the Winkler foundation model, a normalized indentation resistance is independent of the primary belt system parameters - carrying weight per unit width, idler diameter and backing thickness - as is the case for a three-parameter viscoelastic model. Example results are provided for a typical rubber compound backing material and belt system parameters.

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Wang, Fansheng. "The contact condition of viscoelastic contact problems." Journal of Physics: Conference Series 2553, no. 1 (2023): 012066. http://dx.doi.org/10.1088/1742-6596/2553/1/012066.

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Abstract Three contact states in the viscoelastic contact deformation area between the rigid cylinder and the viscoelastic foundation are discussed based on various material mechanical properties between the rigid and the viscoelastic materials. On this basis, the relationship model between the node displacements and the node stresses in the boundary contact area is established, and the corresponding numerical analytical algorithms are used to simulate the viscoelastic contact deformation. Meanwhile, an example is given to simulate the contact deformation of the conveyor belt.

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Silver, Frederick H., Michael Gonzalez-Mercedes, and Arielle Mesica. "A Rapid Method to Noninvasively Measure the Viscoelastic Properties of Synthetic Polymers Using Mechanical Vibrations and Photonics." Photonics 9, no. 12 (2022): 925. http://dx.doi.org/10.3390/photonics9120925.

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Noninvasive measurement of the viscoelastic properties of both natural and synthetic polymers is important for the analysis of implant design and performance as well as in industrial material development. In this study, we used vibrational optical coherence tomography (VOCT) to compare the elastic and viscoelastic properties of silicone polymers with standard tensile stress–strain measurements. VOCT uses acoustic vibrations and infrared light to measure the resonant frequency of viscoelastic materials. The elastic modulus was calculated from the in-phase deformation of the material at fixed frequencies using an empirical calibration curve. Viscous loss was measured after pulsing the samples based on the ratio of mechanovibrational peak widths to heights. The results showed that the optimal cure time and modulus values obtained using VOCT were like those obtained using conventional tensile testing. VOCT could capture results that were comparable to conventional testing while not destroying the material, suggesting its usefulness for in vivo and in situ measurements as well as for early quality control environments during end-use application and fabrication experiments. We conclude that VOCT is a new technique that is comparable to conventional testing for noninvasively and nondestructively measuring the viscoelastic properties of polymers.

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Lewandowski, Roman, and Przemysław Wielentejczyk. "Free vibration of frame structures made of Zener type viscoelastic material." MATEC Web of Conferences 285 (2019): 00009. http://dx.doi.org/10.1051/matecconf/201928500009.

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A method for determining the dynamic characteristics of structures made of viscoelastic material is presented. The fractional Zener model is used to the describe the rheological properties of materials. All of the elements of a structure must be built of material with identical rheological properties. The solution to the linear eigenvalue problem for some elastic structure and the solution to a single nonlinear algebraic equation are needed to obtain the dynamic characteristics of a viscoelastic structure. Moreover, the frequency response functions are determined in a very efficient way. The results of a representative calculation are presented and briefly discussed.

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Sepiani, Hossein, Maria Anna Polak, and Alexander Penlidis. "Finite element implementation of viscoelastic and viscoplastic models." Engineering Computations 37, no. 8 (2020): 2561–85. http://dx.doi.org/10.1108/ec-02-2019-0062.

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Purpose The purpose of this study is to present a finite element (FE) implementation of phenomenological three-dimensional viscoelastic and viscoplastic constitutive models for long term behaviour prediction of polymers. Design/methodology/approach The method is based on the small strain assumption but is extended to large deformation for materials in which the stress-strain relation is nonlinear and the concept of incompressibility is governing. An empirical approach is used for determining material parameters in the constitutive equations, based on measured material properties. The modelling process uses a spring and dash-pot and a power-law approximation function method for viscoelastic and viscoplastic nonlinear behaviour, respectively. The model improvement for long term behaviour prediction is done by modifying the material parameters in such a way that they account for the current test time. The determination of material properties is based on the non-separable type of relations for nonlinear materials in which the material properties change with stress coupled with time. Findings The proposed viscoelastic and viscoplastic models are implemented in a user material algorithm of the FE general-purpose program ABAQUS and the validity of the models is assessed by comparisons with experimental observations from tests on high-density polyethylene samples in one-dimensional tensile loading. Comparisons show that the proposed constitutive model can satisfactorily represent the time-dependent mechanical behaviour of polymers even for long term predictions. Originality/value The study provides a new approach in long term investigation of material behaviour using FE analysis.

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Dardas, Dorota. "Survey of Applicable Methods for Determining Viscoelastic Effects in Ferroelectric and Antiferroelectric Chiral Liquid Crystals." Materials 17, no. 16 (2024): 3993. http://dx.doi.org/10.3390/ma17163993.

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Viscosity, elasticity, and viscoelastic properties are one of the most fundamental properties of liquid crystalline materials; the main problem in determining these properties is the multitude of physical parameters needed to determine the values of elasticity and viscosity constants. In this paper, a number of different measurement methods for the complete characterization of viscoelastic properties for smectic liquid crystalline materials and their mixtures are analyzed, both theoretically and experimentally. The way in which viscoelastic material constants are determined depends mainly on the application/purpose of the materials under study. The subject of this work was to review the methods used to determine viscoelastic effects in ferroelectric and antiferroelectric chiral liquid crystals, their mixtures, composite materials, and even in dielectric systems, which would bear the hallmark of a universal method allowing the application of sufficiently low electric fields. In the case of chiral liquid crystals with ferroelectric and antiferroelectric phases and their subphases, the following assumption applies: fulfilment of Hooke’s law (in the case of elastic coefficients) and preservation of laminar flow (in the case of viscosity coefficients).

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Keenan, Kathryn E., Saikat Pal, Derek P. Lindsey, Thor F. Besier, and Gary S. Beaupre. "A Viscoelastic Constitutive Model Can Accurately Represent Entire Creep Indentation Tests of Human Patella Cartilage." Journal of Applied Biomechanics 29, no. 3 (2013): 292–302. http://dx.doi.org/10.1123/jab.29.3.292.

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Cartilage material properties provide important insights into joint health, and cartilage material models are used in whole-joint finite element models. Although the biphasic model representing experimental creep indentation tests is commonly used to characterize cartilage, cartilage short-term response to loading is generally not characterized using the biphasic model. The purpose of this study was to determine the short-term and equilibrium material properties of human patella cartilage using a viscoelastic model representation of creep indentation tests. We performed 24 experimental creep indentation tests from 14 human patellar specimens ranging in age from 20 to 90 years (median age 61 years). We used a finite element model to reproduce the experimental tests and determined cartilage material properties from viscoelastic and biphasic representations of cartilage. The viscoelastic model consistently provided excellent representation of the short-term and equilibrium creep displacements. We determined initial elastic modulus, equilibrium elastic modulus, and equilibrium Poisson’s ratio using the viscoelastic model. The viscoelastic model can represent the short-term and equilibrium response of cartilage and may easily be implemented in whole-joint finite element models.

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Lee, In-Won, and Nam-Hyun An. "Measurement Method of Complex Dynamic Viscoelastic Material Properties." Transactions of the Korean Society of Mechanical Engineers A 33, no. 5 (2009): 489–95. http://dx.doi.org/10.3795/ksme-a.2009.33.5.489.

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Sridhar, T., and R. K. Gupta. "Material properties of viscoelastic liquids in uniaxial extension." Journal of Rheology 35, no. 3 (1991): 363–77. http://dx.doi.org/10.1122/1.550219.

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Chen, C. P., and R. S. Lakes. "Design of viscoelastic impact absorbers: Optimal material properties." International Journal of Solids and Structures 26, no. 12 (1990): 1313–28. http://dx.doi.org/10.1016/0020-7683(90)90081-6.

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Klapper, I., C. J. Rupp, R. Cargo, B. Purvedorj, and P. Stoodley. "Viscoelastic fluid description of bacterial biofilm material properties." Biotechnology and Bioengineering 80, no. 3 (2002): 289–96. http://dx.doi.org/10.1002/bit.10376.

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Katouzian, Mostafa, and Sorin Vlase. "Mori–Tanaka Formalism-Based Method Used to Estimate the Viscoelastic Parameters of Laminated Composites." Polymers 12, no. 11 (2020): 2481. http://dx.doi.org/10.3390/polym12112481.

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The paper establishes the mechanical properties of a viscoelastic composite material reinforced with fibers, where the fiber is transverse isotropic and the matrix is isotropic (a common case met in engineering practice). A computation method using the Mori–Tanaka mean field method has been developed in order to apply on viscoelastic materials. Using this procedure, the time-dependent response of a viscoelastic composite material can be determined. Schapery’s nonlinear constitutive equation is also used in the compliance matrix determination of the composite material under investigation. Nonlinearity factors were determined by creep tests at different values of stresses and temperatures and for different materials, based on the least squares method. The results obtained experimentally and their comparison with the theoretically obtained values show a good agreement between experiment and calculation.

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Muhammed, Montadher A. "FINITE ELEMENT METHOD FOR INCOMPRESSIBLE VISCOELASTIC MATERIALS." Journal of Engineering 17, no. 1 (2011): 159–72. http://dx.doi.org/10.31026/j.eng.2011.01.13.

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A numerical method (F.E.)was derived for incompressible viscoelastic materials, the aging andenvironmental phenomena especially the temperature effect was considered in this method. Atreatment of incompressibility was made for all permissible values of poisons ratio. Amechanical model represents the incompressible viscoelastic materials and so the properties canbe derived using the Laplace transformations technique .A comparison was made with the othermethods interested with viscoelastic materials by applying the method on a cylinder of viscoelastic material surrounding by a steel casing and subjected to a constant internal pressure, as well as a comparison with another viscoelastic method and for Asphalt Concrete problem exposed to constant pressure (vehicles load) was done. The obtained results was very convenient , as well as, a large time steps can be taken than others methods.

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Ardan, Wildy, Siti Fatimah, and Kartika Yulianti. "Model Relaksasi dan Osilasi Menggunakan Persamaan Diferensial Orde Fraksional Tipe Caputo." KUBIK: Jurnal Publikasi Ilmiah Matematika 7, no. 2 (2023): 61–68. http://dx.doi.org/10.15575/kubik.v7i2.17929.

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The phenomenon of relaxation and oscillation is a common event that is often encountered. Both of these properties can occur in viscoelastic materials even though they do not occur simultaneously. Because the characteristics of viscoelastic materials are difficult to describe using classical-order differential equations, in this study, fractional-order differential equations were used to model each of the relaxation and oscillation phenomena in viscoelastic materials with the help of Laplace transform as a solution method . The solution obtained characterizes the phenomenon of memory effect as well as viscoelastic materials in general. In addition to this phenomenon, several other variables were also found to be the influence of the related material motion dynamics.

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Abusabir, Ahmed, Muhammad A. Khan, Muhammad Asif, and Kamran A. Khan. "Effect of Architected Structural Members on the Viscoelastic Response of 3D Printed Simple Cubic Lattice Structures." Polymers 14, no. 3 (2022): 618. http://dx.doi.org/10.3390/polym14030618.

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Three-dimensional printed polymeric lattice structures have recently gained interests in several engineering applications owing to their excellent properties such as low-density, energy absorption, strength-to-weight ratio, and damping performance. Three-dimensional (3D) lattice structure properties are governed by the topology of the microstructure and the base material that can be tailored to meet the application requirement. In this study, the effect of architected structural member geometry and base material on the viscoelastic response of 3D printed lattice structure has been investigated. The simple cubic lattice structures based on plate-, truss-, and shell-type structural members were used to describe the topology of the cellular solid. The proposed lattice structures were fabricated with two materials, i.e., PLA and ABS using the material extrusion (MEX) process. The quasi-static compression response of lattice structures was investigated, and mechanical properties were obtained. Then, the creep, relaxation and cyclic viscoelastic response of the lattice structure were characterized. Both material and topologies were observed to affect the mechanical properties and time-dependent behavior of lattice structure. Plate-based lattices were found to possess highest stiffness, while the highest viscoelastic behavior belongs to shell-based lattices. Among the studied lattice structures, we found that the plate-lattice is the best candidate to use as a creep-resistant LS and shell-based lattice is ideal for damping applications under quasi-static loading conditions. The proposed analysis approach is a step forward toward understanding the viscoelastic tolerance design of lattice structures.

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Olodo, E. T., E. C. Adjovi, and V. Adanhounme. "Identification of Heredity Kernels and Their Influence on the Life Time of Glass/Polyester Composites." International Journal of Applied Mechanics and Engineering 19, no. 4 (2014): 725–34. http://dx.doi.org/10.2478/ijame-2014-0050.

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Abstract One of the major problems encountered in prediction of hereditary viscoelastic behavior of polymeric composites is the determination of heredity kernels. This issue comes down to identification of the model characterizing the viscoelastic properties of these materials. The purpose of this work is to propose a model for prediction of viscoelastic nonlinear behavior of laminate composite with polyester matrix, through the study and analysis of heredity kernels and their influence on the life time of this material. Identification of this model required experimental determination at room temperature, of viscoelastic parameters of heredity kernels by macroscopic approach. These data provide predictive tools for establishment of the life time and long term stress limit under static complex loading for this type of material.

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Ganser, Christian, Caterina Czibula, Daniel Tscharnuter, Thomas Schöberl, Christian Teichert, and Ulrich Hirn. "Combining adhesive contact mechanics with a viscoelastic material model to probe local material properties by AFM." Soft Matter 14, no. 1 (2018): 140–50. http://dx.doi.org/10.1039/c7sm02057k.

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BÖSE, HOLGER. "VISCOELASTIC PROPERTIES OF SILICONE-BASED MAGNETORHEOLOGICAL ELASTOMERS." International Journal of Modern Physics B 21, no. 28n29 (2007): 4790–97. http://dx.doi.org/10.1142/s0217979207045670.

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Magnetorheological (MR) elastomers are composite materials consisting of magnetic particles in elastomer matrices, whose mechanical properties can be influenced by applying a magnetic field. Main parameters which determine the behavior of these smart materials are the concentration of the magnetic particles and the mechanical stiffness of the elastomer matrix. The viscoelastic properties of silicone-based MR elastomers are outlined in terms of their storage and loss moduli. The mechanical behavior of the material is also influenced by a magnetic field during the curing of the elastomer matrix, which leads to materials with anisotropic microstructures. The storage modulus of soft elastomer matrix composites can be increased in the presence of a magnetic field by significantly more than one order of magnitude or several hundreds of kPa. The relative increase exceeds that of all previously reported data. A shape memory effect, i. e. the deformation of an MR elastomer in a magnetic field and its return to original shape on cessasion of the magnetic field, is described.

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Łabuński, Piotr, and Lucjan Witek. "EXPERIMENTAL ANALYSIS OF DAMPING PROPERTIES OF VISCOELASTIC MATERIALS." Acta Metallurgica Slovaca 27, no. 2 (2021): 63–67. http://dx.doi.org/10.36547/ams.27.2.896.

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This study presents results of an experimental investigations of the materials used in passive damping vibrations. The main purpose of this paper was to examine the damping properties of selected viscoelastic materials (VEM), using the modal analysis. In presented analysis three configurations of specimens were considered. At first, the separated steel beam was analyzed. As results of this analysis, the frequencies and amplitudes of the beam during resonance were obtained. In next part of the work the modified specimen was investigated. In this modification the bitumen-based material (as a damper) was fixed to the surface of the beam. This method is known as free layer damping (FLD) treatment. In last configuration, the butyl rubber layer was connected to the steel beam. Using the Unholtz-Dickie UDCO-TA250 electrodynamic vibration system, the natural frequencies and amplitudes of free vibrations for all examined specimens were obtained. The vibration amplitude of the beam was measured using piezoelectric acceleration sensors. In order to define the damping capabilities of both the bitumen based material and the butyl rubber, the relative amplitude of specimens and the loss factor using half-power bandwidth method were calculated.

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Zhao, Li Jie, and Qiang Fu. "Parametric Study of EAPap Material Properties." Advanced Materials Research 430-432 (January 2012): 242–46. http://dx.doi.org/10.4028/www.scientific.net/amr.430-432.242.

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Cellulose paper is used as base material for so-called electroactive papers (EAPap) actuator. EAPap is a complex anisotropic material, which has not been extensively characterized and additional basic testing is required before developing application devices from EAPap. Mechanical properties of EAPap were investigated in this work under different environmental conditions (humidity, temperature, and electrical field) and configurations. It shows viscoelastic effect and exhibits two distinct elastic and plastic modulus connected by a bifurcation point. Through tests, environment and configuration effects on EAPap are obtained to researchers and designers interested in the field of smart materials and EAP.

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Kosenko, Ekaterina, Natalya Baurova, and Vladimir Zorin. "Creation of Basalt Plastics with Different Types of Hybrid Matrices." Materials Science Forum 1037 (July 6, 2021): 189–95. http://dx.doi.org/10.4028/www.scientific.net/msf.1037.189.

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Basalt plastic, thanks to its complex of valuable operational properties, has a potential variety of applications. the article describes the technology of production of basalt plastics with various types of hybrid matrices, one of the components of which is cured in the molding process, and the second-like a binder in natural materials, retains its viscoelastic state. The viscoelastic component makes it possible to increase the deformation properties in the zones of their location, preventing cracking under increased loads. As a result of the conducted mechanical tensile tests, the average values of absolute breaking forces, tensile strength and elongation during fracture of basalt plastic samples with different types of hybrid matrices were obtained. The addition of viscoelastic components (such as technical wax, anaerobic, and organosilicon polymer materials) to the basalt plastic matrix allows to increase the elongation at fracture by 2...5%. Anaerobic polymer material in the basalt plastic matrix allows to increase the tensile strength of the composite material, as well as significantly reduce the dispersion of the measured values. This provides an effective prediction of the operational properties of the structural material in the design of products. On the basis of microanalysis of the structure of basalt plastics with different types of hybrid matrices, an explanation of the causes of changes in the mechanical properties of the resulting composite materials is given.

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Journal articles on the topic 'Viscoelastic material properties'

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