Research on Mechanical Performance Parameter of Metal Rubber
Metal Rubber is special materials and used in aerospace, especially under extreme conditions. It has characteristics of strong adaptability, corrosion resistance, radiation resistance and designability. In this paper, we have manufactured Metal Rubber components, and done some research on the influence of previous deformation to Metal Rubber material's structure and performance, its characteristic parameters such as Poisson's ratio, Elastic modulus were studied. Research results are basic but essential for finite element analysis of Metal Rubber materials; these results also play an important role of engineering application.
Constants of Metal Rubber Material
Damping materials made of pressing wire, such as Metal Rubber (MR material), “metal-flex”, “spring cushion” etc. are used widely in vibration protection systems. They have high strength and damping, however they are non-linear and anisotropic. To use contemporary finite element software for calculation of vibration insulators made of wire damping material one should know constants of this material. Till this time this problem almost isn’t researched, there is only a few data in linear approximation. A Young modulus for pressure and bending, shear modulus, Poisson ratio, friction force for pressure and for shear, friction coefficient between wire material and steel plate are obtained for MR material made of stainless steel wire for different load directions by static experiment in the present research. An influence of deformation, relative density, wire diameter, pressing force, deformation in other direction on these constants is considered. Peculiarities of pressing wire material deformation process are discussed: a difference of Young modulus for pressure and bending, a stabilization of hysteretic loop for one direction during load in another direction, an energy dissipation coefficient for different load directions. Results of the present research not only allow calculation of vibration isolator made of MR material by finite element software, but give a method for research of other pressing wire damping materials.
Response of a base excited system with Coulomb and viscous friction
Abstract The response of a single degree of freedom spring-mass system with viscous and Coulomb friction, with harmonic base excitation, is determined. Closed form analytical solutions of the equation of motion are found for two cases: (a) continuous motion of the mass and (b) motion of mass with two stops per cycle. Results are presented in non-dimensional form as magnification factors versus frequency ratios as functions of viscous and Coulomb friction parameters.