Metal Rubber Material Research Articles

Structural design and dynamic analysis of a metal rubber composite gear pair

This paper introduces a metal rubber composite gear for gear vibration reduction. A comprehensive structural design calculation program is developed for the metal rubber composite gear pair. The design incorporates a gap between the tooth ring and the hub to accommodate thermal expansion and contraction, ensuring smooth transmission without jamming or seizing. The design process takes into consideration the compression and damping properties of the metal rubber material. A significant variable in the design process is the relative density of the metal rubber material. It is utilized to calculate the torsional stiffness, starting friction torque, and dynamic performance of the composite gear pair. To guide and optimize the design process, a nine-degree-of-freedom dynamic model is employed for dynamic analysis. The vibration reduction effect of the metal rubber composite gear is validated through numerical simulations and experimental testing. The results confirm the efficacy of the gear in reducing vibrations. This paper provides valuable insights and guidance for future designs focused on gear vibration reduction, paving the way for further advancements in this field.

Dynamic Characteristics of M-Shape Metal Rubber-Coated Pipeline System: Numerical Modeling and Experimental Analysis

As a high-temperature resistant damping material, reducing vibration by coating with M-shape metal rubber (MMR) in a pipeline system is a promising solution due to its energy dissipation induced by micro dry friction between metallic wires. The main challenge for dynamic calculation and performance evaluation of elastic-porous metal rubber (MR) is derived from the intricate spatial network structure. In this work, the dynamic properties including acceleration admittance and insertion loss of the MMR-coated pipeline system were conducted by numerical simulation and experimental analysis. The constitutive models used to characterize hysteresis phenomena, including Yeoh and Bergström–Boyce models, were identified with different density parameters and adopted for steady-state dynamic numerical analysis. The sine sweep frequency test was conducted to verify the accuracy of the developed numerical model. The results indicate that the maximum error of stress–strain curve between numerical prediction and experimental measurement is 10.7%. In the frequency range of 0–1 500[Formula: see text]Hz, the insertion loss of the MMR-coated pipeline system is positively correlated with the density of MMR, as opposed to the coating distance of pipeline clamps and the influence of excitation force is minimal. Furthermore, the error of dynamic response of the pipeline system in low frequency between the experiment and simulation is 4.7%, indicating that the accuracy of the hysteresis model in predicting the dynamic characteristic of MR materials is effective.

Research on mechanical properties of metal rubber based on planar lattice design

Metal rubber is a common vibration is olation material. Because the arrangement of the internal spiral coil will affect the mechanical properties of the metal rubber, this paper draws on the crystal lattice theory in metallurgy, changes the mesoscopic arrangement of the spiral coil through the design of the two-dimensional blank plane lattice structure, and prepares three kinds of lattice structures, and optimizes the mass ratio of the three metal rubber lattice structures, so as to improve the average stiffness and energy dissipation coefficient of the metal rubber. The quasi-static compression experiments passed. The results show that the triangular lattice structure design can reflect the good average stiffness, and the square lattice structure design can obtain the maximum energy dissipation coefficient. The study confirms that the fabrication of metal rubber materials based on planar lattice design is an effective way to improve stiffness and energy dissipation.

Equivalent linearization of hyperelastic rubber rings in dynamic vibration absorber boring bar and simulation of its dynamic properties

A slight perturbation in high-speed precision cutting could cause violent vibration of boring bars, resulting in unexpected wear and failure of the structures. In this paper, the dynamical characteristic of a boring bar with a dynamic vibration absorber (DVA) is investigated. Considering that the nonlinear characteristics of the rubber ring play a significant role in improving the capacity of DVA, we proposed an equivalent linearization method for modeling hyperelastic rubber rings based on the experimental data of uniaxial tensile test. The relationship between the stiffness of rubber rings and the precompression parameter δ is established for two types of rubber. The equivalent linearization model shows good accuracy and calculation efficiency while the mass of the DVA is confined to a narrow space and the assumption of small strain is inherently satisfied. Numerical results show that the time cost of the equivalent linearization model is only 5% of the full hyperelastic model. Furthermore, the effect of different spring stiffnesses and damping on the dynamic characteristics of the boring bar is compared by using the equivalent linearization model, and the vibration peak of the DVA boring bar is found to be reduced about 45%. Our findings establish a simplified modeling scheme for choosing rubber rings in design of dynamic vibration absorbers with acceptable accuracy and little time cost, which could also give some reference for modeling of metal rubber and gel-like materials.

Semi-active vibro-acoustic control of vehicle transmission systems using a metal rubber-based isolator

This work is concerned about employing a semi-active metal rubber (MR)-based isolator to suppress noise and vibration for vehicle transmission systems. The adaptive stiffness and damping properties of MR material play a key role in the semi-active control effect. In this regard, a particular automotive transmission component—precisely, a plate dedicated to accommodating bearings—has been selected as the focus of research to control its noise and vibration. A microcomputer-driven control system is applied, featuring characteristics such as high performance, compact size, lightweight design, and energy efficiency, which make it ideal for testing in the automotive sector. The efficacy of the devised control scheme is assessed through the deployment of accelerometers and sound intensity probes to quantify the vibrations and the radiated acoustic power, respectively. Interesting noise and vibration reduction rates are achieved using both open-loop and closed-loop strategies. This research opens the horizons to employ MR material in a semi-active configuration for industrial requirements surpassing its classical passive implementation, notably in terms of broadband attenuation performance.

Numerical modeling and topological analysis of entangled single-wire metal rubber

Metal rubber materials, formed by entangling single metal wires and also known as ESW-MR, have attracted widespread attention due to their unique non-linear load curves and excellent environmental adaptability. The mechanical behavior of these materials, which are created through the weaving or winding of pure metal wires, is influenced by the structural characteristics of semi-flexible fiber cross-linked fibers. This study delves deeply into the microstructure of ESW-MR, with the aim of establishing a numerical model that can accurately simulate and characterize its structure. A method based on arbitrarily defined baselines parametric equations in the global space was adopted, leading to the creation of a parametric model for a continuously wound wire with multiple spiral mechanisms. Finite element simulations based on explicit dynamics were conducted using LS-DYNA and could successfully simulate the cold stamping forming process of ESW-MR blanks. The model was validated through stamping and quasi-static tests, as well as computed tomography (CT) scan tests. The results demonstrate the model accuracy in describing the macroscopic and microscopic characteristics of the material, showing excellent agreement with the actual material. Furthermore, the study successfully extracted the micro-topological features of the material, providing additional quantitative information on the topological characteristics of ESW-MR. This work offers a valuable tool for the study and application of ESW-MR and presents a novel perspective for the numerical simulation of a wide range of entangled materials. It paves the way for gaining a deeper understanding of the microstructure and mechanical behavior of such materials.

Semi-analytical dynamic modeling of parallel pipeline considering soft nonlinearity of clamp: A simulation and experimental study

Clamp is a crucial support structure to secure and connect the parallel pipeline system. Since the metal felt of the clamp is composed of metal rubber material, as well as the clamp structure using bolted connections, clamp is prone to cause nonlinear force during vibration. Nevertheless, no relevant paper has been reported to study the influence of soft nonlinearity of clamps on parallel pipelines. To bridge this gap, the present study introduces a novel semi-analytical dynamic model that effectively considers the influences of nonlinear clamps in parallel pipeline systems. The proposed model simulates the clamp's vertical hysteretic restoring force using the Bouc-Wen model. The clamp parameters are identified using Particle Swarm Optimization (PSO) with experimental and simulation errors as the objective function. Subsequently, the model is then validated by conducting modal and response tests. The numerical results are consistent with the experimental results. In order to prove the validation of the proposed model, experiments are conducted using dual clamps at different positions, and it can be observed that the nonlinear parameters of the clamps still meet the accuracy requirements. Moreover, the influences of fluid parameters on frequency are compared with the ANSYS software and the proposed model, and the influence trends exhibit consistency. By considering the nonlinear effects of clamps, the proposed model facilitates enhanced accuracy in predicting vibration responses.

Application of metal rubber for semi-active vibration control of mechanical transmission systems

This study proposes a novel semi-active vibration control technique for mechanical transmission systems. The backbone of current research technology is the adaptive stiffness and damping properties of metal rubber (MR) which plays the role of tuning to the vibrational system eigenmodes. The adaptive properties of MR material were proved by a previous study, but the present research investigates the effect of this feature on the structural response and designs an MR-based semi-active vibration controller for industrial application. For this purpose, the semi-active control strategy is created based on an optimal tuning using experimental harmonic test results. The control strategy is applied in practice using a linear actuator controlled by a double pole double throw (DPDT) relay, and National Instruments hardware and software for reading data and writing the control task. The isolator attachment position is defined through the analysis of eigenmode shapes that are predetermined by numerical simulation. A maximum isolation rate of 55.17% is measured near the vibration isolator position. It is observed that the isolation position has a prominent effect on structure vibration behavior where the elastic wave has been reduced in amplitude by passing the isolator position. The effectiveness of the MR-based semi-active control approach is eminent and its application for vibration isolation of commercial mechanical transmission systems could be studied in the future.

Constitutive relation expansion of large load metal rubber engine mount stress bivariate function relationship using the strain and strain rate

Metal rubber materials were first used for vibration cushioning and noise protection applications in aviation equipment. With the recent developments in science and technology, metal rubber materials have been gradually implemented in Vehicle Vibration Suppressing. Metal rubber has significant advantages over ordinary rubber materials, in terms of its vibration damping in extreme environments. Along these lines, the objective of this work was to develop a mechanical model of metal rubber mount for mining vehicles, which can be used to predict the equivalent stress change of large load metal rubber mount in actual operation. Starting from the mechanical model of the mount and then expanding the macroscopic one-dimensional relationship of force and displacement to the binary relationship between the force and displacement and velocity, the microscopic one-dimensional relationship of stress and strain was expanded to the binary relationship between the stress and strain and strain rate. This work focused on the three-dimensional intrinsic structure model of stress, strain, and strain rate for metal rubber mounts. Moreover, the mechanical properties of the metal rubber mounts were explored in conjunction with the Mooney–Rivlin model, while the constitutive relationship of its stress, strain, and strain rate was deduced. The three-dimensional hysteresis curves were plotted by using software simulation analysis of the metal rubber mounts, and the metal rubber mounts hysteresis surface was also fitted. A combination of simulated and experimental data was used to test the accuracy of the proposed mechanical model of the metal rubber mount. From the acquired results, it was demonstrated that the errors of the relevant parameters (c10,c01, and c11) of the mechanical model of the metal rubber mount were about 10%. On top of that, the errors of the simulated stiffness values and the damping ratios of the metal rubber mount and the experimental stiffness values and damping ratios were within 10%. Excluding the interference of the metal rubber mount fabrication error, the proposed mechanical model met the mechanical analysis of the metal rubber mount with a large load and the mechanical model was accurate. The influence of the strain and strain rate on the stiffness and damping of the metal rubber mounts was also clarified, and the expansion method of the constitutive relationship of the metal rubber mount stress and strain was systematically explored. From the analysis of the metal rubber mounts’ mechanical properties, a reference basis for its vibration analysis and for the mechanical analysis of other nonlinear materials was provided.

Hysteresis dynamic model of metal rubber based on higher-order nonlinear friction (HNF)

Metal rubber (MR) is a kind of porous and highly elastic pure metal damping material, but its strong nonlinear hysteresis characteristics are the main factors limiting its engineering application. In this paper, a high-order nonlinear friction (HNF) model was proposed for the first time according to the inclination angle and contact form of the spatial distribution of metal wires in MR. At the same time, combined with nonlinear elastic restoring force, nonlinear damping force, and coulomb hysteresis friction force, a general hysteresis dynamic model of MR was constructed. In order to verify the accuracy of the model, three kinds of MR with different densities were prepared and tested. The results show that the HNF hysteresis dynamic model has a very high prediction accuracy (R2= 0.9999) and a high signal-to-noise ratio (SNR > 700). The hysteresis curve of the HNF hysteresis dynamic model was highly consistent with the experimental hysteresis curve, while the accuracy and versatility of the traditional dynamic model decreased with the change of density. It is because the HNF term includes the influence factors that can characterize the contact form of the metal wire inside MR and the material properties. These influence factors will be adjusted in real-time to reduce the error of the model according to the changes in the preparation process parameters or material properties. Therefore, the HNF hysteresis dynamic model could effectively demonstrate the nonlinear hysteresis characteristics of MR and had the adaptive ability to change process parameters. This paper provided a new theoretical model for the dynamic system of MR materials with a complex network structure.

Design and mechanical properties of cervical fusion cage based on porous entangled metal rubber material.

Titanium and its alloys are one of the mainstream materials for the manufacture of intervertebral cages. With the application on clinical, the problems of elastic modulus is relatively high, subsidence of adjacent vertebral implants and stress shielding after surgery have gradually exposed. In this paper, metal rubber made from titanium alloy wire was used to prepare cervical fusion cage (CFC), which was a porous material with buffering and vibration damping properties. The C5/C6 segment of the goat cervical vertebra was used as the research object. The shape parameters of the CFC were determined by combining the three-dimensional model data of the cervical vertebra and the structural characteristics of the natural intervertebral disc. The force of CFC under different working conditions were simulated and analyzed by finite element simulation. Then three kinds of metal rubber core (MRC) were prepared by medical titanium alloy wire (TC4), and their mechanical properties and fatigue strength were experimentally studied. With the increases of density, the mechanical properties of MRC improved. The variation range of the loss factor η under different amplitudes and frequencies were 20% and 16.3%, respectively. After one million vibrations, the wear rate was 0.131g/MC; after five million vibrations, the wear rate was 0.158g/MC, which was similar to the existing clinical prosthesis wear rate. The MRC has sufficient mechanical strength. Compared with the existing clinical prostheses, it has a longer service life and has broad application prospects.

Fretting wear evolution model of the metal filaments inside metal rubber

Metal rubber (MR) is a porous material which possesses macroscopic damping properties through the dry friction between the internal helical metal wires. Due to its complex topological structure, the research on the fretting wear of MR is rarely reported in the literature. In the present work, a double-body wear model of metal filaments is constructed by the master-slave composite method. The friction and wear conditions of the dynamic and static metal wires inside the MR are analyzed under different contact angles, loads, and vibration amplitudes. The results indicate that the wear area and volume of the dynamic wire under each working condition are significantly larger than those of the static wire, while the case for the wear depth is the opposite. After wear, the wires exhibit an obvious stress concentration phenomenon, which is distributed along the wire wear contour area, and the wear profile has a high sensitivity to the contact angle. In order to further investigate the difference in the wear degree of the static and dynamic wires inside the MR, the fretting amplitude is introduced to describe the wear scar area of the dynamic wire, the special wear scar area is reorganized regularly, and the wear volume of the wire is approximated by the regional combination, deriving and constructing a fretting wear evolution model suitable for MR wires. This evolution model can simultaneously predict the wear degree of dynamic and static wires, and its prediction accuracy is high. The prediction accuracy under each working condition is basically less than 10%; thus, the proposed model can be effectively applied to the fretting wear prediction of MR ultra-fine wire contact pairs. This work provides theoretical guidance for the life prediction and other aspects of MR materials.

Experimental research on the friction and leakage of the metal rubber seal for reciprocating motion

Metal seals are widely used to solve the sealing problem in severe conditions. For reciprocating motion sealing problems, a metal rubber seal was proposed by combining the metal rubber (MR) materials with an axial opening C-shape jacket. In this research, to study the reciprocating sealing performance of metal rubber seals, a series of leaking experiments were carried out with a dynamic sealing test system. The friction force of the MR seal was measured under a variety of hydraulic pressure and velocity conditions. The static leakage principle of MR seals for axial sealing was presented based on Persson’s contact mechanics, and a circular gap leakage model was employed to describe the leakage during reciprocating motions. The static and dynamic leakage experiments of metal rubber seals for axial sealing were conducted, and the influence factors of leakage rates were analyzed.

An Experiment on the Mechanical Properties of Metal Rubber Processed by Improved Processing Techniques and the Construction of Its Constitutive Relation

To figure out the performance of dampers made of metal rubber (MR) that are installed in bridge and frame shear wall structures to change the energy consumption mode of artifacts, experiments were performed on the MR material processed by improved processing techniques to test its compression and shear hysteresis properties in high-temperature environment, and discover the laws of the impact of factors such as the improved processing techniques and temperature on the compression and shear hysteresis of the material. At the same time, based on test curves and the strain hardening laws of the material, this paper employed the least square method to perform piecewise linear fitting on MR curves, and the corresponding strain hardening constitutive model was established and verified. The study suggests that, after processed by the improved processing techniques, the compression and shear hysteresis energy consumption performance of the MR test pieces is very stable, and the shear strength had been improved. As the temperature increases, the metal rubber consumes more vibrational energy, and the stiffness of MR vibration isolator increases as well; at a same temperature, as the strain amplitude and relative density increase, the vibrational energy consumed by the MR damping material increases accordingly. The simplified constitutive model constructed in the paper has a simple form, it can not only describe the strain hardening features of the material, but also conform to the test curves, therefore, it can facilitate the parameter design and the calculation of MR dampers. The research conclusions obtained in this paper can provide theoretical and experimental evidence for the processing, preparation, and application of MR dampers, and it is of very important theoretical significance and practical value.

Predicting Nonlinear and Anisotropic Mechanics of Metal Rubber Using a Combination of Constitutive Modeling, Machine Learning, and Finite Element Analysis.

Metal rubber (MR) is an entangled fibrous functional material, and its mechanical properties are crucial for its applications; however, numerical constitutive models of MR for prediction and calculation are currently undeveloped. In this work, we provide a numerical constitutive model to express the mechanics of MR materials and develop an efficient finite elements method (FEM) to calculate the performance of MR components. We analyze the nonlinearity and anisotropy characteristics of MR during the deformation process. The elasticity matrix is adopted to express the nonlinearity and anisotropy of MR. An artificial neural network (ANN) model is built, trained, and tested to output the current elastic moduli for the elasticity matrix. Then, we combine the constitutive ANN model with the finite element method simulation to calculate the mechanics of the MR component. Finally, we perform a series of static and shock experiments and finite element simulations of an MR isolator. The results demonstrate the feasibility and accuracy of the numerical constitutive MR model. This work provides an efficient and convenient method for the design and analysis of MR components.

Optimization on hysteresis dynamic model of metal rubber material based on dry friction damping term

As one kind of porous elastic metal material, metal rubber is used in vibration isolation widely due to its better damping characteristic. During loading and unloading, the elastoplastic deformation and damping characteristics of this material are usually described by constructing its dynamic model. Although traditional models can describe the hysteresis performance, the accurate parameter identification of material structure under different preparation conductions is limited due to its complex expression or equivalent math form. In this paper, a dynamic hysteresis model is optimized through adding a dry friction damping term based on the micro-element analysis theory and analysis method of material mesoscopic structure. The relation among the manufacture technic, size of metal wire and vibration parameters were established, which accurately describes hysteresis characteristic of metal rubber by dry friction when the metal wires are in the state of slipping contact. The result is verified by the harmonic vibration experiment that the model has good adaptability and convenience, especially can improve the accuracy and convenience of parameter identification on the forming materials of metal rubber.

ХАРАКТЕРНЫЕ СЛУЧАИ УДАРНОГО НАГРУЖЕНИЯ ВИБРОЗАЩИТНЫХ СИСТЕМ АГРЕГАТОВ И УЗЛОВ ТРАНСПОРТНЫХ СРЕДСТВ

Using the previously developed mathematical model of a vibration isolator with an elastic–hysteresis element made of metal–rubber material and the obtained approximate solutions of the nonlinear differential equation of the aircraft motion based on the Bubnov–Galerkin methods and a small parameter, the dependences for constructing shock–insulating characteristics for rectangular and semi–sinusoidal pulses are derived. It is shown that the error of these solutions in comparison with the exact solutions for some elastic characteristics, in particular, with a significant nonlinearity in the form of a cubic parabola, does not exceed 3.5%.

ИССЛЕДОВАНИЕ ОКОЛОРЕЗОНАНСНЫХ РЕЖИМОВ ВЫНУЖДЕННЫХ КОЛЕБАНИЙ ВИБРОЗАЩИТНЫХ СИСТЕМ С КОНСТРУКЦИОННЫМ ДЕМПФИРОВАНИЕМ ПРИ ГАРМОНИЧЕСКОМ ВОЗБУЖДЕНИИ

Using the previously developed mathematical model of a vibration isolator with an elastic – hysteresis element made of metal–rubber material and on the basis of the Bubnov–Galerkin method, the solution of the equation of forced vibrations of vibration protection systems (VS) under harmonic excitation is obtained. The obtained theoretical results are used to construct generalized dynamic characteristics of vibration isolators with structural damping, in particular, vibration isolators with an elastic–hysteresis element made of MR material. As a result, a simple and fairly general procedure for calculating the generalized vibration–isolating characteristics of the aircraft for the case of harmonic linearization is obtained.

Experimental investigation on enhanced mechanical and damping performance of corrugated structure with metal rubber

Abstract A new type of sandwich construction with the metal rubber-filled corrugated hybrid core (MR-CHC) which was manufactured by filling the trapezoidal metal rubber materials into the interstices of corrugation, was proposed and it's structural characteristics were investigated via experimental method in present study. The quasi-static out-of-plane compressive experiments were carried out to study the stiffness and energy absorption ability of the sandwich construction. It is demonstrated that the compressive stiffness, the compressive strength and the energy absorption ability of MR-CHC composite structure are higher than those of empty corrugated core sandwich structure as well as single metal rubber material, and increase with the increasing relative density of metal rubber (MR). In addition, under the harmonic load, the hysteresis behavior of MR-CHC sandwich structure was investigated and found that the tangent modulus and loss factor of MR-CHC sandwich structure are significantly affected by the relative density of MR filler and the key experimental parameters including the amplitude, the pre-compression level and the excitation frequency. The loss factor of sandwich structures with MR-CHC ranges from 0.1 to 0.16, which is higher than that of single MR material and sandwiches with empty corrugated core. Furthermore, the effects of the relative density of MR filler and the experimental parameters on the tangent modulus and the loss factor of MR-CHC sandwich structure were discussed by associating the mechanical properties of sandwich construction with the contact states of the helix wires.

Study on the Mechanical Properties of Metal Rubber with Complex Contact Friction of Spiral Coils based on Virtual Manufacturing Technology

Metal rubber (MR) is an elastic porous material with a complex spiral network structure, which is widely used in aerospace, aviation, navigation, medical biomaterials, and other fields. The traditional preparation processes depend on multiple tests or artificial experience, which leads to time‐consuming and laborious. Herein, a virtual manufacturing method is proposed to realize the spatial multipoint dynamic contact analysis of a complex spiral network structure, that is, to study the mechanical properties of MR from the micro‐tribological point of view. Through real‐time capturing the spatial distribution characteristics of each contact point and the number of contact pairs and contact mode, it is found that the number of dry friction contact points between the wires is nonlinear positive correlation with the damping energy dissipation characteristics of MR. The preparation parameters, such as the wire diameter, the spiral wire pitch, and the blank winding angle, are selected to be investigated, and the controlling variable method is used to analyze the single factor influence in the virtual preparation process. The results show that the damping and energy consumption characteristics of MR can be improved effectively by reducing the wire diameter, by reducing the spiral wire pitch, or by increasing the winding angle of the blank. However, too small or too large preparation parameters cause stress concentration and affect the mechanical properties of the actual materials. The quasi‐static compression test is carried out through the preparation of the products, and the error between simulation and experiment results is <8%. Herein, the mechanism of contact friction between wire turns in MR is expounded. Also, this method can effectively guide the production of MR material, reduce the time of material design, and promote the popularization and application of the material.