Development and thermal-mechanical evaluation of a rotation-controlled magnetorheological clutch based on a dual-layer Halbach array

Magnetorheological (MR) fluids, as a class of novel smart materials, offer continuously adjustable yield stress capabilities for structural transmission and vibration control. However, balancing high torque density with low operational temperature rise remains a critical bottleneck for MR composite-based structural devices. To address this issue, this study proposes an MR clutch with a rotation-controlled dual-layer Halbach array structure, which enables precise control of high torque while significantly suppressing temperature rise. Based on the Bingham–plastic model, the theoretical torque transmission of the clutch was derived. Finite element simulations were conducted to systematically analyze the magnetic field distribution, shear yield stress, viscosity characteristics, and the transient and steady-state thermal behavior within the gaps. On the basis of the aforementioned design and simulation analysis, a prototype of the proposed MR clutch was fabricated. Experimental tests were carried out to evaluate the torque–speed characteristics and thermal performance. The results show that the clutch can output a torque of 8.5 N·m. The simulated temperature rise in the working gaps is merely 6.5 °C after 5 min of continuous operation. The proposed MR clutch exhibits strong potential for long-term stable operation under low-speed conditions, offering a novel design pathway for high-performance MR transmission devices.