Misalignment-modulated magnetoelastic transduction for field-tunable stiffness in chain-like magnetorheological elastomers: a Green-function-weighted traction-transfer framework
2053-1591
Abstract
Magnetorheological elastomers (MREs) are field-responsive composites whose stiffness can be tuned by a magnetic field. In chain-like MREs, strong local magnetic interactions and Maxwell tractions do not necessarily translate into a measurable macroscopic response, because interfacial tractions may be internally balanced after elastic propagation. This study develops a Green-function-weighted traction-transfer framework describing how generalized misalignment modulates magnetoelastic transduction. Local interfacial magnetic traction is projected onto a prescribed macroscopic observable through an output-specific elastic influence field, and a transfer-efficiency index quantifies the contribution that survives weighted cancellation. A minimal two-source model and a dimensionless illustration show that misalignment can produce an output through magnetic-traction imbalance, elastic-transfer imbalance, or their combination, whereas compensating imbalances suppress it. A three-dimensional strong-field finite-element study (flux density up to 0.58 T, constant relative permeability µ _r = 200) resolves two effects in aligned and longitudinally offset chains under tension, compression, and shear: a strongly mode-dependent magneto-induced effect, reaching +36.0% in shear while tension is weak (+6.4%) and the compressive nominal stress is reduced, and an output-specific geometric effect in which, at matched strain, field, and particle volume fraction, the offset chain is stiffer in shear and compression while the two configurations are essentially equal in tension. The solver is verified against an analytic single-sphere solution (0.13% error) and a zero-field hyperelastic degeneracy test (0.0003% error). The transfer-efficiency index is evaluated directly from the finite-element fields and cross-validated against the macroscopic reaction force, giving near-unity transfer in the field-aligned channel and near-complete cancellation in the cross-mode channel. The framework yields a design guideline rather than a universal rule: enhancement occurs only when misalignment increases the product of available weighted traction and transfer efficiency for the selected output.