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An elastic-porous composite with Cu-steel bimetallic wire mesh was proposed to meet the requirements of damping, vibration reduction, and electrical conductivity of aerospace hardware equipment. Firstly, the samples with different weight ratios (Cu/steel) were prepared through special manufacturing processes: composite wire preparing, helical coil encircling, stretching with equal pitch, entangling in an interlocked pattern, and cold stamping. Secondly, the mechanical performances such as stiffness, loss factor, and tangent modulus were characterized by the static compression test. Thirdly, the sensitivity of electrical conductivity to the loading force was examined by mechanical-electrical coupling tests. Finally, the influence of the weight ratio (Cu/steel) on the mechanical and electrical properties was discussed. The results show that the Cu elements can generally improve the damping capacity and reduce the stiffness of the material. The resistance-force curves of specimens show obvious nonlinearity, and the resistance decreases with the increase of compression force. The conductivity of the materials increases with the increasing stiffness and weight ratio according to the resistance-stiffness curves.

Metal rubber is a new type of elastic damping material. It’s often used in all kinds of instruments and equipment to vibration isolation and buffer. The internal of metal rubber is mesh structure in space formed with wires. The contact points of the crossed wires aren’t solid collusion. Although the compressive strength of metal rubber is very good, but the structure of metal rubber would become loosly and destroyed under tensile load. Literature [1] put forward that the pulse discharge sintered to metal rubber can make the contact point transform to solid collusion. The method is based on the theory of resistance welding to the contact points between sintering metal wires in metal rubber. The research and analysis to the electricity characteristics of the metal rubber has important significance to optimize parameters of electrical pulse discharge experiment and improve the quality of sinter.

To meet the need of damping material at the marine corrosive environment, the clamped-edge disk type of metal rubber specimen is designed and its corrosion-load alternate experiment is performed, the anti-corrosive and damping characteristic of the material at the marine corrosive environment is researched. The experimental results show that the corrosive rate of 304 stainless steel metal rubber specimen at cycle-immersion corrosion-load alternate environment is the highest and its decay rate of dynamic average rigidity is also the highest, and followed by full-immersion, cycle-salt-spray and full-salt-spray environment. The damping characteristic of metal rubber specimen is relatively stable at the corrosion-load alternate experiment; the metal rubber material has anti-corrosion ability at marine environment.

Knitted-dapped metal rubber was developed to solve problems of metal rubber with low stiffness and test samples with different sizes were manufactured. Static tests and dynamic tests were carried out to study influences of density and thickness on the static stiffness and influences of frequency, amplitude and preload on dynamic characteristics. Results show that static stiffness rises when density or thickness increases. Frequency has little influence on dynamic characteristics. Knitted-dapped metal rubber will have smaller stiffness and better characteristics of damping, if amplitude increases; if preload increases, energy consumed in the vibration will be more.

Dynamic load experiments of the disc-shaped metal rubber isolation component are performed. Through analyzing variation law of the parameters with amplitude and frequency, which are stiffness coefficient, damping coefficient and damping component factor, the hysteresis restoring force model which is able to fully reveal the dynamic characteristics of the component is established. The experimental verification results show that the theoretic calculations are consistent with the experimental data, which verifies the practicability and effectiveness of mathematical model and parameter identification. It has important practical significance for design of vibration isolation component with different requirements.

In order to study how the parameters of floating slab track and the speed of the train influence the vehicle-track coupling system，the paper built the vehicle-track coupling dynamic system. In the coupling model, the train is simplified a multi-rigid body system. The rail and the floating slab are considered as Euler beam. The wheel-rail relation is regarded as non-linear Hertz contact. The paper solved the dynamic equation of the vehicle-track coupling dynamic system with prediction-correction Newmark-β numerical integration method. Through numerical simulation, the paper gained the affect of fastener stiffness, slab support stiffness, and the speed of train to the characteristic of the coupling system containing the vehicle acceleration, wheel-rail force, the vibration of the track and the counter-force from the basis. The paper provides a reference for the selection of the track parameters and the speed of vehicle.

Vibration can influence the imaging quality and tracking precision of the moving opto-electronic platform seriously, some measures of reducing vibration must be taken into consideration. In this paper the influence which vibration works on the imaging quality is analyzed, a novel design scheme of the damping mechanism is proposed, two new type Metal Rubber Isolators are designed, and two dimensional dynamic angle measuring instrument using linear CCD is applied to measure the dynamic rotational displacement of the opto-electronic platform. The result of vibration sweeping experiment shows that the isolator mechanism can reduce the three axis’ vibration higher than 25Hz. The angle-measurement result presents that the maximum rotational displacement is , which is suited to the demands of the imaging experiment.

The fatigue damage test of metal rubber vibration isolator is performed, the result of which shows that fatigue damage performance of metal rubber is different from conventional solid materials. The damage of metal rubber which is accumulated with its inner partial broken and wore wires, results in deterioration of its macro-mechanical characteristic, macro-cracking and final fatigue failure, so it does not rupture as sudden failure of solid material. It is difficult to describe damage evolution of metal rubber in the microscopic perspective, and from a macro point of view, it is feasible method to describe degree of fatigue damage which bases on the changes of mechanical properties. In order to reflect the incremental cumulative damage degree of metal rubber, the stiffness damage and damping damage are used to accurately describe the fatigue damage process of metal robber, and the comprehensive damage factor is proposed to be the fatigue failure criterion. Damage factor can predict fatigue life of metal rubber specimen accurately, so it has reference significance to design of metal rubber

The damaging variable was defined firstly, mean while the fatigue character of metal rubber was discussed. Then the relationship between damaging variable and cyclic loading times had been summarized through fatigue tests. Finally observed the pattern of fracture face, cavities and flaws of the fatigue wires inner the metal rubber components with electronic scanning microscope, some technical methods of improving the wearing resistivity of metal rubber material had been brought forward.

The damaging factor was defined firstly, mean while the fatigue character of metal rubber was discussed. Then the relationship between damaging factor and cyclic loading times had been summarized through fatigue tests. Finally observed the pattern of fracture face, cavities and flaws of the fatigue wires inner the metal rubber components with electronic scanning microscope, some technical methods of improving the wearing resistivity of metal rubber material had been brought forward.

Metal Rubber is a kind of material with nonlinear of resuming force. In the dynamic test of Metal Rubber based on the control of displacement loading, its force-displacement curve is a hysteretic loop. The hysteretic phenomenon is studied with the means theory and experiment in this paper. The generalized restoring force is the binary function of displacement and speed. For the binary function, it is unilateral to represent the hysteretic loop only on the displacement-force plane, so the space hysteretic loop is introduced. The important parameters of the linear vibration isolators are stiffness and damping coefficient, however the nonlinear vibration isolators have stiffness and damping function, which all need be identified from the tested data. The results have proved that the dynamic model can meet the requirements of dynamic analysis of Metal Rubber in engineering.

Metal rubber material is a new type of elastic and porous material which develops from metal materials. The macro-structure of metal rubber is reticular just as high polymer, made up of fine metal wires. In this paper, the testing equipment which can test micro-motion of metal rubber is designed and the compressive force-displacement curve along molding of metal rubber has gain. The cure along molding of metal rubber has three different characteristic stages. In different characteristic stages, the deformation of metal rubber material has different micro physical mechanism. The micro physical mechanism of different deformation periods is summarized by the micro analyses of three different characteristic curve stages and the study of metal rubber molding technology. Based on the manufacture technology and molding process, the spring wires in metal rubber material have contacted adequately after molding. The micro physical mechanism of metal rubber material in this stage is produced by blank tear combination deformation in linear elastic of spring wires. Because of the deformation stage is very little; the stiffness of metal rubber material is represented linear characteristic in this stage. The contacted points of spring wires are slide along with deformation increasing. The stiffness of metal rubber material is reduced after early linear deformation stage. The compressive force-displacement curve represents soft characteristic stage in macro- expression. When the most contacted points of spring wires are slide along with deformation increasing, the stiffness of metal rubber material is rapid rise. The exponential reinforcement stage is caused by the strongly constraints among spring wires. The micro physical mechanism can explain the different characteristic stages of metal rubber material on compressive performance.

Analysed the stress-strain test in the pressing direction of metal rubber specimen, the deformation process can be divided into three stages. Used the accumulative method of high step polynomial, the experience formula of metal rubber’s deformation character can be simply and effectively established. With the fabrication and formation technology, the microscopic physics mechanism has been analyzed in these deformation stages.

By introducing ZrO2 (3Y) micron powder into the thermit, Al2O3/18%, 21%, 24%, 27% and 30%ZrO2 composite ceramics were obtained from in-situ growth in the melts produced by combustion synthesis. As the volume fraction of ZrO2 is below 27%, the ceramics is comprised of lath-shaped and rod-shaped α-Al2O3 matrix, within the rod-shaped grain the nano-micron fibers are oriented in essentially the same direction. As volume fraction of ZrO2 is over 27%, the ceramics is mainly composed of lamina-shaped grains with alternating α-Al2O3 and t-ZrO2 layers. The flexural strength and the fracture toughness measured simultaneously the maximum values with increasing volume fraction of ZrO2 to 24%, indicating that flexural strength and fracture toughness are simultaneously under the control of rod-shaped grains in which ZrO2 nano-micron monocrystal fibers are embedded.

New nano-submicron textured Al2O3-ZrO2 ceramic eutectic composites were obtained from high-temperature melts produced by the SHS metallurgical process with intro-granular and 1-3 composite structures. Nano-micron textured ceramic composites were naturally self-assembled in one quick step by the SHS metallurgical process, in-situ synthesis and symbotic eutectic transformation under high degree of undercooling. The experimental results indicated that the Al2O3-ZrO2 ceramic eutectic composites with ZrO2 fibers at the nano-submicron scale are only suitable for the ceramic composite with hypoeutectic composition under the conditions of the experiment.

Al2O3/24%ZrO2 composite, which is mainly composed of lath-shaped and rod-shaped α-Al2O3 matrix containing ZrO2 nano-micron fibers, was obtained from in-situ growth in the melts produced by combustion synthesis. The results from XRD, SEM and EPMA showed that, besides the rod-shaped and lath-shaped α-Al2O3 grains, there are also t-ZrO2 or m-ZrO2 independent phases and Cr metallic particles at the boundaries of rod-shaped grains. The strength and toughness were measured to be 1186 MPa and 12.8MPa·m0.5 respectively. The procedure for toughening ceramics relies on coordinated action of multiple toughening mechanisms involving reinforcement-induced toughening by ZrO2 nano-micron fibers, deflection-induced toughening, stress-induced transformation toughening, crack-bridging toughening by lath-shaped α-Al2O3 grains as well as deformation-induced toughening by Cr metallic particles, and promises the occurrence of a sharp rising R-curved behavior.