Co-optimized axial cutting design of galfenol magnetostrictive rods balancing elastic modulus constraints and eddy current suppression

Abstract In order to address high-frequency eddy current losses in Galfenol rods for magnetostrictive transducers, this study proposes an axial cutting optimization strategy and establishes a dual-constraint theoretical model. Through COMSOL Multiphysics simulations and experimental validation, axial cutting has been found to significantly reduce losses by longitudinally disrupting eddy current paths compared to radial cutting: peak loss density decrease from 6.07 × 10 5 mW m −3 (radial) to 1.54 × 10 5 mW m −3 (axial) under 6-lamination conditions, achieving a 74.6% reduction. A quantitative model linking lamination count and rod diameter is developed based on the elastic modulus attenuation threshold (≤5%) and eddy current suppression saturation effects. Experimental results demonstrated that a 6 mm-diameter rod with 6 laminations achieved 95.25% eddy current suppression with only 4.9% elastic modulus degradation. The study reveals a magneto-mechanical coupling mechanism where suppression efficiency plateaus (Δ N < 1%) beyond a critical lamination count, and proposes a dual-objective optimization framework balancing mechanical integrity and electromagnetic performance. These findings provide theoretical foundations for low-loss design in miniaturized high-frequency transducers.