High-speed videomicroscopy and magnetorheology under triaxial unsteady magnetic fields Martínez-Cano, Óscar Morillas Medina, José Rafael Ruiz-Nievas, J. Camacho Villar, Guillermo Rodríguez Barroso, Alejandro Ramírez, J. Vicente Álvarez-Manzaneda, Juan De We describe a custom-built device that is capable of superimposing triaxial unsteady magnetic fields on a sample at the same time that its microstructure is visualized using a high-speed camera and its rheological properties are measured with a commercial rheometer. The device reaches field strengths up to 5 kA · m−1, frequencies up to 4 kHz, and its functionality is evaluated by testing magnetorheological fluids under steady shear flow and field transients. Striking differences are found at small Mason numbers by changing the field configuration. 2025-04-07T11:05:24Z 2025-04-07T11:05:24Z 2025-02-13 journal article Phys. Rev. E 111, 025415 (2025) [DOI: https://doi.org/10.1103/PhysRevE.111.025415] https://hdl.handle.net/10481/103494 10.1103/PhysRevE.111.025415 eng info:eu-repo/grantAgreement/EC/H2020/MSCA/101030666 http://creativecommons.org/licenses/by/4.0/ open access Atribución 4.0 Internacional American Physical Society