Investigation on field-response performance of magnetic-sensitive rubber by impact experiments with adjustable magnetic fields

A magnetic-sensitive rubber (MSR) can change its stiffness and damping characteristics with variant magnetic intensity. Hence, it is possible to use it in dissipating the impact energy adaptively. Although the relationships between elastic modulus, damping ratio and magnetic intensity have been investigated extensively by static tensile, compression or shear experiments as well as vibration tests, few literatures have shown the effectiveness of MSRs on energy dissipating during impact. In this present paper, a group of magnetic-sensitive specimens, composed by ferromagnetic particles with various volume fraction, particle dimensions at millimeter-scale or micrometer-scale, particle arrangement in chain-like or uniform distributions, and rubber matrix with three different types were manufactured. Then, a series of impact experiments aimed to test the capability of MSRs in mitigating shock was conducted by a self-developed drop hammer device with adjustable homogeneous magnetic field. The influences of the above factors on the acceleration responses were investigated. To explain the mechanism, the mathematical model of the impact process was established, and based on it; the acceleration response was obtained by MATLB software. The numerical solutions are validated by comparing with the corresponding test results. It is found that the volume fraction of particles and magnetic intensity has the obvious influences on the dynamic acceleration response, while the arrangement of macro-particle in matrix affects less. Micro-particles can change the characteristics of matrix more significantly than the macroparticles.