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In order to meet the demand of three-way vibration reduction of metal rubber, a pot-shaped metal rubber was designed and prepared via introducing spatial configuration. The method of controlling variables to study the effect of preparation process parameters such as relative density, forming angle, wire diameter and compression on the static mechanics of pot-shaped metal rubber was investigated, and the influence of three preparation process parameters on the pot-shaped metal rubber axial and radial static mechanics was revealed by orthogonal test method. The results show that the sequence that affects the axial static mechanical properties of the test piece is forming angle, relative density, and wire diameter; the sequence that affects the radial static mechanical properties of the test piece is relative density, wire diameter, and the forming angle.

Interpenetrating phase composites (IPCs) with porous metal materials as the matrix and polymer materials as the reinforcement, which have a broad application prospect, have both the high strength of metal materials and the high energy absorption capacity of polymer materials. Entangled metallic wire materials are a new type of porous material with damping characteristics, which is an excellent choice for use as the matrix of IPCs. In the present work, a novel entangled metallic wire material–silicone rubber IPC is developed through the vacuum infiltration method with the entangled wire material as the matrix and silicone rubber as the reinforcing element. The mechanical properties (loss factor and tangent modulus) of the as-synthesized composites are characterized through compression tests. More specifically, the effects of key experimental parameters (strain) and material properties (matrix density, wire diameter, and anisotropy) on the mechanical properties of the composites are analyzed in detail. It is found that with the introduction of interfacial friction, the loss factor of the composites becomes higher than those of the pure entangled metallic wire material and silicone rubber; in particular, the tangent modulus is significantly enhanced. The complex structural characteristics of the proposed composite enable the loss factor and tangent modulus to exhibit a nonlinear relationship with the density over a range of displacement values. Moreover, the smaller the wire diameter is, the greater the loss factor of the composites is, while the tangent modulus exhibits the opposite trend. The unique wire contact form and preparation process endow the composites with nonlinear properties in the molding direction as well as pronounced anisotropy characteristics. A novel interpenetrating phase composite is proposed. The composite quasistatic curve is nonlinear with excellent mechanical properties. The improved energy consumption properties are due to the interfacial friction. The increase in wire density greatly improves the elastic modulus of the composite. The composite is anisotropic with a better bearing capacity in the molding direction. [ABSTRACT FROM AUTHOR]

This work presents the experimental characterization and improved model of multi-strand entangled metallic wire materials (MS-EMWMs). MS-EMWM is a novel damping material made of several strands of entangled wires using a modified manufacturing process. Six batches of specimens were fabricated and tested under quasi-static loading. Secant stiffness and loss factor were calculated to indicate the mechanical properties. The results showed that MS-EMWM has the characteristics of high damping energy dissipation compared to EMWM. A micro-multi-strand spiral spring model was proposed to predict the mechanical properties of MS-EMWM. The probability distribution of micro-spring pairs between wires was used to characterize the random combination of materials. According to the results, the improved model can effectively reflect the mechanical behavior of MS-EMWM. The mechanical properties of MS-EMWM were predicted by the coefficient matrix obtained by particle swarm optimization. Through the prediction and test results, the predicted results are acceptable. [ABSTRACT FROM AUTHOR]

In the present work, a facile one-step methodology was used to synthesize honeycomb-like BiFeO3/g-C3N4 composites, where the well-dispersed BiFeO3 strongly interacted with the hg-C3N4. The 10BiFeO3/hg-C3N4 could completely degrade RhB under visible light illumination within 60 min. The degradation rate constant was remarkably improved and approximately three times and seven times that of pristine hg-C3N4 and BiFeO3, respectively. This is ascribed to the following factors: (1) the unique honeycomb-like morphology facilitates the diffusion of the reactants and effectively improves the utilization of light energy by multiple reflections of light; (2) the charged dye molecules can be tightly bound to the spontaneous polarized BiFeO3 surface to form the Stern layer; (3) the Z-scheme heterojunction and the ferroelectric synergistically promoted the efficient separation and migration of the photogenerated charges. This method can synchronously tune the micro-nano structure, surface property, and internal field construction for g-C3N4-based photocatalysts, exhibiting outstanding potential in environmental purification. [ABSTRACT FROM AUTHOR]

Aiming at the vibration reduction problems of pipeline systems under high temperature, a high temperature mechanics model of the metal rubber coated damping structure of the pipe-lines was established by equivalent linearization method. The model was used for analyzing the stiffness and response amplitude of metal rubber treated with different temperatures. The thermal-vibration joint test system of the pipelines was set up firstly. Then the damping performance of the coated damping structure of the pipelines was verified with different ambient temperatures and metal rubber densities, where the insertion loss was taken as the evaluation index. The results show that reducing he density of metal rubber may effectively increase the vibration attenuation effectiveness of the pipelines. At the same time, the effect of the ambient temperature on the metal rubber coated damping structure is negligible, indicating that the coated damping structure may work well in a high temperature environment. [ABSTRACT FROM AUTHOR]