Artículos de revistas: "Multiaxial dissipation"

1

Kolenda, Janusz. "Dissipation energy in viscoelastic solids under multiaxial loads". Polish Maritime Research 15, n.º 1 (1 de enero de 2008): 19–28. http://dx.doi.org/10.2478/v10012-007-0047-4.

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Dissipation energy in viscoelastic solids under multiaxial loads On the basis of the three-dimensional constitutive equations for strains resulting from the Kelvin-Voigt's model and modified Hooke's law for multiaxial stress in viscoelastic solids, the formulae for the energy dissipated in a given time per unit volume have been derived. It is shown that after application or removal of triaxial static load there is no difference in the time functions governing the dissipation of strain energy of volume change and the dissipation of strain energy of distortion. Harmonic in-phase stress and harmonic out-of-phase stress as well as multiaxial periodic stress are also considered. It is demonstrated that in the process of energy dissipation due to normal and shear stress components the role of the latter is dominant.

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2

Gosar, Aleš y Marko Nagode. "Energy dissipation under multiaxial thermomechanical fatigue loading". International Journal of Fatigue 48 (marzo de 2013): 223–30. http://dx.doi.org/10.1016/j.ijfatigue.2012.10.021.

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3

Arnold, S. M., A. F. Saleeb y T. E. Wilt. "A Modeling Investigation of Thermal and Strain Induced Recovery and Nonlinear Hardening in Potential Based Viscoplasticity". Journal of Engineering Materials and Technology 117, n.º 2 (1 de abril de 1995): 157–67. http://dx.doi.org/10.1115/1.2804523.

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Specific forms for both the Gibb’s and the complementary dissipation potentials were chosen such that a complete potential based multiaxial, isothermal, viscoplastic model was obtained. This model, in general, possesses three internal state variables (two scalars associated with dislocation density and one tensor associated with dislocation motion) both thermal and dynamic recovery mechanisms, and nonlinear kinematic hardening. This general model, although possessing associated flow and evolutionary laws, is shown to emulate three distinct classes of theories found in the literature, by modification of the driving threshold function F. A parametric study was performed on a specialized nondimensional multiaxial form containing only a single tensorial internal state variable (i.e., internal stress). The study was conducted with the idea of examining the impact of including a strain-induced recovery mechanism and the compliance operator, derived from the Gibb’s potential, on the uniaxial and multiaxial response. One important finding was that inclusion of strain-induced recovery provided the needed flexibility in modeling stress-strain and creep response of metals at low homologous temperatures, without adversely affecting the high temperature response. Furthermore, for nonproportional loading paths, the inclusion of the compliance operator had a significant influence on the multiaxial response, but had no influence on either uniaxial or proportional load histories.

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4

Jana, Prasun y Anindya Chatterjee. "Modal damping in vibrating objects via dissipation from dispersed frictional microcracks". Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 469, n.º 2152 (8 de abril de 2013): 20120685. http://dx.doi.org/10.1098/rspa.2012.0685.

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Many materials under multiaxial periodic loading exhibit rate-independent internal dissipation per cycle. Constitutive modelling for such dissipation under spatially variable triaxial stresses is needed for calculating modal damping of solid bodies using computational packages. Towards a micromechanically motivated model for such dissipation, this paper begins with a frictional microcrack in a linearly elastic solid under far-field time-periodic tractions. The material is assumed to contain many such non-interacting microcracks. Single-crack simulations, in two and three dimensions, are conducted using ABAQUS. The net cyclic single-crack dissipation under arbitrary triaxial stresses is found to match, up to one fitted constant, a formula based on a pseudostatic spring-block model. That formula is used to average the energy dissipation from many randomly oriented microcracks using Monte Carlo averaging. A multivariate polynomial is fitted to the Monte Carlo results. The polynomial is used in finite-element simulation of a solid object, wherein modal analysis is followed by computation of the net cyclic energy dissipation via elementwise integration. The net dissipation yields an equivalent modal damping. In summary, starting from a known formula for a single crack, this paper develops and implements a method for computationally modelling the modal damping of arbitrarily shaped solid bodies.

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5

Rigon, Daniele, Filippo Berto y Giovanni Meneghetti. "Crack paths in multiaxial fatigue of C45 steel specimens and correlation of lifetime with the thermal energy dissipation". Frattura ed Integrità Strutturale 16, n.º 59 (22 de diciembre de 2021): 525–36. http://dx.doi.org/10.3221/igf-esis.59.34.

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The work reports the observed fatigue damage of C45 steel specimens tested in a previous work under multiaxial loading conditions and its relationship with the thermal energy dissipation which has been used in the last decades to estimate the uniaxial fatigue behavior of metals. For this purpose, fatigue data relevant to thin-walled samples made of quenched and tempered C45 steel tested under completely reversed combined axial and torsional cyclic loadings with different biaxiality ratios and phase-shift angles have been analysed. The analyses of crack paths at the initiation point of failure were performed after a 50% stiffness loss that corresponded to a crack size ranging from 7 to 15 mm; afterwards, the characteristic crack paths of each loading condition were analysed by using a digital microscope to identify the orientation of the crack initiation plane. After having broken all fatigue tested specimens under static tensile loading, the fracture surfaces were inspected close to the crack initiation point using a digital microscope. Despite the stress states and fatigue damage mechanisms dependent on the load condition, the Q parameter applied to the present experimental results proved to correlate all multiaxial fatigue test results in a single fatigue scatter band.

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6

Feng, E. S., X. G. Wang y C. Jiang. "A new multiaxial fatigue model for life prediction based on energy dissipation evaluation". International Journal of Fatigue 122 (mayo de 2019): 1–8. http://dx.doi.org/10.1016/j.ijfatigue.2019.01.003.

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7

Nourian-Avval, A. y M. M. Khonsari. "A new model for fatigue life prediction under multiaxial loadings based on energy dissipation". International Journal of Fatigue 151 (octubre de 2021): 106255. http://dx.doi.org/10.1016/j.ijfatigue.2021.106255.

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8

Rigon, D., F. Berto y G. Meneghetti. "Estimating the multiaxial fatigue behaviour of C45 steel specimens by using the energy dissipation". International Journal of Fatigue 151 (octubre de 2021): 106381. http://dx.doi.org/10.1016/j.ijfatigue.2021.106381.

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9

Zhang, Jun, Hai-Yu Li, Hong Jia y Hui Li. "Analysis of dissipation energy and ratchetting behaviors on multiaxial fatigue of adhesively bonded joints". Engineering Failure Analysis 120 (febrero de 2021): 105107. http://dx.doi.org/10.1016/j.engfailanal.2020.105107.

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10

Rigon, Daniele, Vittoria Formilan y Giovanni Meneghetti. "Analysis of the energy dissipation in multiaxial fatigue tests of AISI 304L stainless steel bars". Procedia Structural Integrity 13 (2018): 1638–43. http://dx.doi.org/10.1016/j.prostr.2018.12.344.

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11

Saleeb, Atef F., Binod Dhakal, Santo A. Padula y Darrell J. Gaydosh. "Calibration of a three-dimensional multimechanism shape memory alloy material model for the prediction of the cyclic “attraction” character in binary NiTi alloys". Journal of Intelligent Material Systems and Structures 24, n.º 1 (21 de septiembre de 2012): 70–88. http://dx.doi.org/10.1177/1045389x12457255.

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As typically utilized in applications, a particular shape memory alloy device or component operates under a large number of thermomechanical cycles, hence, the importance of accounting for the cyclic behavior characteristics in modeling and characterization of these systems. To this end, the present work is focused on the characterization of the evolutionary, cyclic behavior of binary 55NiTi (having a moderately-high transformation temperature range). In this study, an extensive set of test data from recent cyclic, isobaric, tension tests was used. Furthermore, for the calibration and characterization of this material, a newly developed, multiaxial, material-modeling framework was implemented. In this framework, multiple, inelastic mechanisms are used to regulate the partitioning of energy dissipation and storage governing the evolutionary thermomechanical response.

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12

Gu, Qingheng, Guangming Zhao, Xiangrui Meng, Jian Sun, Xiang Cheng, Wensong Xu y Ruofei Zhang. "Creep Behavior and Its Prediction of Saturated Weakly Cemented Medium-Grained Sandstone under Multiaxial Loadings". Geofluids 2023 (6 de febrero de 2023): 1–9. http://dx.doi.org/10.1155/2023/3747027.

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Weakly cemented medium-grained sandstone in Ordos mining area of China is widely distributed under phreatic water. The creep behavior of saturated rock is important for the stability of water-resisting strata. In this paper, creep mechanical properties of saturated medium-grained sandstone were studied by triaxial rheological test. The results showed that medium-grained sandstone only shows attenuation creep and stable creep under low stress level, and accelerated creep occurs when axial load reaches about 75% of instantaneous compressive strength. The rock samples exhibit volume dilatancy under most loading levels and finally shear fracture. The failure mechanism is the dislocation separation of mineral particles. Based on the energy dissipation theory, the damage evolution equation was modified and introduced into the Burgers model, which can accurately describe the rheological behavior of saturated medium-grained sandstone. The modified model was used to predict the crack initiation time under different deviatoric stresses, which can provide guidance for early warning of water-resisting rock stability.

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13

Ding, Zhi Ping, Ming Li, Teng Fei Wang y Rong Hua Yang. "Analysis of Multiaxial Low Cycle Fatigue Life for Single Crystal Ni-Based Superalloy Based on Two-Phase Unit Cell Model". Applied Mechanics and Materials 117-119 (octubre de 2011): 503–8. http://dx.doi.org/10.4028/www.scientific.net/amm.117-119.503.

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Based on micro structure of Ni-based single crystal superalloy, a γ/γ’ two-phase unit cell finite element model was established, and its cyclic stress-strain was simulated under tension/torsion cyclic loading. A low cycle fatigue (LCF) life prediction model of single crystal superalloy was proposed by using cyclic plasticity strain energy as a parameter based on energy dissipation theory. Calculation results of macro finite element model and γ/γ’ two-phase unit cell micro finite element model, and multiaxial LCF test data of CMSX-2 Ni-based single crystal superalloy along [001] orientation were applied to fit the LCF life model by multiple linear regression. The results show that the unit cell model not only reflects the microstructure characteristics of single crystal Ni-based superalloy, but also is better than the macro model in accuracy of analysis, and greatly improve the accuracy of fatigue life prediction. Almost test data fall into the factor of 2.0 scatter band.

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14

Schäfer, Benjamin Josef, Petra Sonnweber-Ribic, Hamad ul Hassan y Alexander Hartmaier. "Micromechanical Modelling of the Influence of Strain Ratio on Fatigue Crack Initiation in a Martensitic Steel-A Comparison of Different Fatigue Indicator Parameters". Materials 12, n.º 18 (4 de septiembre de 2019): 2852. http://dx.doi.org/10.3390/ma12182852.

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Micromechanical fatigue lifetime predictions, in particular for the high cycle fatigue regime, require an appropriate modelling of mean stress effects in order to account for lifetime reducing positive mean stresses. Focus of this micromechanical study is the comparison of three selected fatigue indicator parameters (FIPs), with respect to their applicability to different total strain ratios. In this work, investigations are performed on the modelling and prediction of the fatigue crack initiation life of the martensitic high-strength steel SAE 4150 for two different total strain ratios. First, multiple martensitic statistical volume elements (SVEs) are generated by multiscale Voronoi tessellations. Micromechanical fatigue simulations are then performed on these SVEs by means of a crystal plasticity model to obtain microstructure dependent fatigue responses. In order to account for the material specific fatigue damage zone, a non-local homogenisation scheme for the FIPs is introduced for lath martensitic microstructures. The numerical results of the different non-local FIPs are compared with experimental fatigue crack initiation results for two different total strain ratios. It is concluded that the multiaxial fatigue criteria proposed by Fatemi-Socie is superior for predicting fatigue crack initiation life to the energy dissipation criteria and the accumulated plastic slip criteria for the investigated total strain ratios.

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15

Kim, Min Sook y Young Hak Lee. "Seismic Performance of Reinforced Concrete Columns Retrofitted with Hybrid Concrete Jackets Subjected to Combined Loadings". Materials 15, n.º 18 (7 de septiembre de 2022): 6213. http://dx.doi.org/10.3390/ma15186213.

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In the existing reinforced concrete columns where they are insufficient seismic details, critical failure mode such as shear failure can be observed under seismic loads. One strategy for the retrofitting of existing concrete columns is to use concrete jacketing. Concrete jacketing consists of a new concrete layer with longitudinal and transverse reinforcements, and can improve seismic resistance capacity. In this paper, a detail of concrete jacket that can be expected for easy construction and improved adhesion performance of longitudinal and transverse reinforcement was proposed. Additionally, a combined cyclic loading test was conducted to consider the seismic load with multiaxial characteristics. The concrete jacket details utilize three components: Steel Grid Reinforcement (SGR), Steel Wire Mesh (SWM), and Steel Fiber Non-Shrinkage Mortar (SFNM). One RC column with non-seismic details and two jacketed RC columns were fabricated to demonstrate the construction efficiencies and structural capacities of the jacketed columns. Two details of jacketed section were considered as variables. It was observed that the specimens retrofitted with concrete jacket resisted torsional load more than the un-retrofitted specimen in terms of crack and failure mode. The experimental results showed that the maximum load of retrofitted specimens was increased by more than 8 times compared to the un-retrofitted specimen, regardless of the jacket details. Newly designed concrete jacket effectively increased the strength. Compared with the un-retrofitted column, the columns retrofitted with the proposed details achieved significant increase in initial stiffness and energy dissipation.

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16

Michopoulos, J. G., A. P. Iliopoulos, J. C. Steuben y J. C. Hermanson. "Multiaxial and Multiscale Implications of Dissipative Behavior of Composites". IOP Conference Series: Materials Science and Engineering 388 (19 de julio de 2018): 012005. http://dx.doi.org/10.1088/1757-899x/388/1/012005.

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17

Li, C. G. y P. S. Steif. "Multiaxial Cyclic Response of Filled Rubber". Rubber Chemistry and Technology 73, n.º 2 (1 de mayo de 2000): 193–204. http://dx.doi.org/10.5254/1.3547584.

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Abstract Cyclic response of filled rubber to simultaneous combinations of shear and extension is studied experimentally. Both in-phase (elastic) and out-of-phase (dissipative) portions of the response are measured for simple shear, uniaxial tension, and combinations of the two. As noted by other researchers, the response is nonlinear, with a strong dependence on strain amplitude. However, it is shown that the response to tension and to combinations of strains can be approximately related to the response to simple shear. Such correlations are useful in predicting the response of rubber-based components subjected to complex strain cycles when only experimental data on shear is available.

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18

Sweeney, John, Paul Spencer, Glen Thompson, David Barker y Phil Coates. "Constitutive Modelling of Polylactic Acid at Large Deformation Using Multiaxial Strains". Polymers 13, n.º 17 (31 de agosto de 2021): 2967. http://dx.doi.org/10.3390/polym13172967.

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Sheet specimens of a PLLA-based polymer have been extended at a temperature near to the glass transition in both uniaxial and planar tension, with stress relaxation observed for some time after reaching the final strain. Both axial and transverse stresses were recorded in the planar experiments. In all cases during loading, yielding at small strain was followed by a drop in true stress and then strain hardening. This was followed by stress relaxation at constant strain, during which stress dropped to reach an effectively constant level. Stresses were modelled as steady state and transient components. Steady-state components were identified with the long-term stress in stress relaxation and associated with an elastic component of the model. Transient stresses were modelled using Eyring mechanisms. The greater part of the stress during strain hardening was associated with dissipative Eyring processes. The model was successful in predicting stresses in both uniaxial and planar extension over a limited range of strain rate.

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19

Wang, Xiaoran, Jinhua Wang, Xin Zhou, Xiaofei Liu y Shuxin Liu. "Mechanical Behaviors and Precursory Characteristics of Coal-Burst in Deep Coal Mining for Safety-Sustainable Operations: Insights from Experimental Analysis". Sustainability 16, n.º 5 (3 de marzo de 2024): 2103. http://dx.doi.org/10.3390/su16052103.

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Coalburst, a frequent and severe dynamic disaster, poses significant challenges to the safety and sustainable development of coal mines during deep excavation. To investigate the mechanical behaviors and precursory characteristics of coalburst subjected to in situ stress conditions, multiaxial cyclic loading experiments were conducted on cubic coal specimens, and the effects of different confining pressures on the mechanical parameters and energy evolution were analyzed. Acoustic emission (AE) technology was utilized to study the accumulation process of stress-induced damage and identify the source modes of microcracks. Then, nonlinear fractal theory and critical slowing theory were used to investigate the time-varying precursory characteristics of catastrophic failure in coalburst. The results show that as the confining pressure increases, the coal samples exhibit higher levels of elastic strain energy and dissipative energy, indicating an enhancement of plasticity. The AE count and accumulated energy show a strong correlation with cyclic loads. With an increasing number of cycles, the AE Felicity ratio gradually decreases, indicating a progressive increase in irreversible damage. Shear-mode microcracks also become more prominent with applied stress and confining pressures, as supported by varying AF/RA values of AE signals. The AE signals also follow the Hurst statistical law, and increasing applied stress and confining pressure strengthen this statistical pattern with a higher Hurst index. Throughout the cyclic loading process, certain AE varying trends were observed: the autocorrelation coefficient increased, the fractal dimension gradually decreased, and the variance suddenly increased. These trends serve as early, middle, and short–imminent warning signals, respectively, for the catastrophic failure of the loaded coal sample. These research findings contribute to a deeper understanding of coal failure evolution and provide a basis for early detection and warning of coalburst disasters, which are also essential for promoting the safe and sustainable development of deep coal mining operations.

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20

Eriten, Melih, Ahmet D. Usta y Lejie Liu. "Tuning the Dissipation in Friction Dampers Excited by Depolarized Waves Across Patterned Surfaces". Journal of Vibration and Acoustics 138, n.º 5 (26 de mayo de 2016). http://dx.doi.org/10.1115/1.4033343.

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Recently, patterned surfaces (elastodynamic meta-surfaces) were shown to cause mechanical wave depolarization resulting in conversion of uniaxial waves to multiaxial vibrations. Frictional oscillators loaded in multiple directions provide more tailorable damping scheme when compared to uniaxially loaded equivalents. This paper utilizes wave depolarization properties of patterned surfaces in tuning frictional damping. In particular, two-dimensional (2D) motion achieved by anisotropic wave reflection and depolarization across patterned surfaces is exerted on a simple friction oscillator; and frictional energy dissipation is studied using the homogenization theory and mechanics of a simple friction oscillator under macro and microslip conditions. The degree of depolarization is shown to control the extent of frictional shakedown (no-dissipation) zones and magnitude of energy dissipation for different incident wave frequencies and amplitudes. Transmission of the depolarized waves from the patterned surface to the friction oscillator enables higher and more uniform frictional damping for broader loading conditions. Uniform damping facilitates predictive linear dynamic models, and tuning the magnitude of damping permits efficient and robust wave attenuation, and energy transfer and localization in dynamic applications. A discussion on modeling assumptions and practical utilization of this potential is also provided. The presented potential of tuning frictional dissipation from very low to high values by simple surface patterns suggests that more sophisticated surface patterns can be designed for spatially varying frequency-dependent wave attenuation.

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21

Feng, Ensheng, Xiaogang Wang y Chao Jiang. "Multiaxial fatigue evaluation of type 316L stainless steel based on critical plane and energy dissipation". Fatigue & Fracture of Engineering Materials & Structures, 30 de agosto de 2022. http://dx.doi.org/10.1111/ffe.13822.

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22

Yazdani, Siamak, Amin Salehi, Ashkan Saboori, Babak Jahani y Svenn Borgersen. "DAMAGE MODELING AND ASSESSMENT FOR BRITTLE MATERIALS". Proceedings of International Structural Engineering and Construction 4, n.º 1 (julio de 2017). http://dx.doi.org/10.14455/isec.res.2017.170.

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Observed nonlinearities in frictional and brittle solids such as concrete, rocks, ceramics, and some composites arise mainly due to the nucleation and propagation of microvoids and microcracks. Microcrack formation, propagation, and coalescence damage the material and renders it more compliant. Microdefects and cracks are also usually irreversible and cause strong anisotropy in the response to loads. This paper presents a damage mechanics model to capture material anisotropy and damage under multiaxial stress states for proportional and fatigue type loadings. The theory is cast within the generally accepted principles of thermodynamics with internal variables where the dissipation inequality is invoked to develop loading surfaces. Flow rules for the onset of inelastic deformations is provided and specific damage laws are proposed. The model extension to the cyclic and fatigue type loading is presented and numerical results are provided with comparison to the available experimental data.

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23

Apetre, Nicole, Attilio Arcari, John Michopoulos, Evan Strickland, Steven Rodriguez, Athanasios P. Iliopoulos, John Steuben y Benjamin Graber. "Towards Fatigue-tolerant Design of Additively Manufactured Strut-based Lattice Metamaterials". Journal of Computing and Information Science in Engineering, 28 de marzo de 2024, 1–19. http://dx.doi.org/10.1115/1.4065201.

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Abstract The advent of additive manufacturing (AM) has enabled the prototyping of periodic and non-periodic metamaterials (a.k.a. lattice or cellular structures) that could be deployed in a variety of engineering applications where certain combinations of performance features are desirable. For example, these structures could be used in a variety of naval engineering applications where light-weight, large surface area, energy absorption, heat dissipation, and acoustic bandgap control are desirable. Furthermore, combining the multifunctional design optimization of these structures with progressive degradation due to cyclic loading could lead to fatigue-activated attritable systems with potentially tailorable performances not yet in reach by current conventional systems. Nevertheless, in order to deploy these complex geometry structures their multiphysics response has to be well understood and characterized. The objective of the current effort is to describe an initial approach for designing a uniaxial metamaterial specimen for fatigue testing as the first step toward the design of multiaxial fatigue test coupons. In order to compare bending- and stretching-dominated structures, two strut-based lattices made of Ti-6Al-4V alloy consisting of the octet and tetrakaidecahedron (or Kelvin) cells are examined. The specimens are designed to fail in the central area of the specimen where edge effects are minimized. Finite element results of the relevant structural mechanics are implemented and exercised to compare the performance of the four relevant geometries and to evaluate the effect of relative density on fatigue life.

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Artículos de revistas sobre el tema "Multiaxial dissipation"

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