Hard–Soft–Hard Magnetic Laminated Magnetorheological Elastomers: Paving the Way to High Bidirectional Modulus Regulation and Superior Mechanical Properties

With the increasing demand for vibration isolation in advanced manufacturing, precision instruments must not exhibit significant vibrations under broadband excitation, necessitating real-time stiffness adjustment in vibration isolation systems to effectively isolate external low and high-frequency vibrations. Magnetorheological elastomer (MRE) semiactive vibration isolators can adapt well to broadband environments, but current bidirectional modulus regulation methods are either overly complex or ineffective. Modifying the internal MRE is the most direct and effective approach. Achieving pronounced bidirectional modulus regulation while maintaining mechanical properties and MR effects in MREs is a current research challenge. This study creatively used a stratified curing method to fabricate an anisotropic laminated MRE (L-MRE) with hard magnetic MRE (H-MRE) on both ends and conventional MRE in the middle layer. The SEM, EDS, XRM, and optical imaging confirmed the successful fabrication of L-MRE. Theoretical analysis and testing validated that L-MRE seamlessly integrates the magnetic and mechanical advantages of H-MRE and MRE, showcasing great advantages of the complementary effect of composite materials. Most importantly, compared to traditional MRE materials, the lamination effect endows L-MRE with satisfactory bidirectional modulus regulation. This research provides an innovative material with reference value for the application demands of broadband vibration reduction technology.