Design, fabrication and testing of a magnetorheologic fluid braking system for machine tool application

Abstract

This technical article introduces a governable brake system that can be relevant for different machines, developed using magnetorheologic (MR) fluids. As an initial step, new MR fluids are developed considering different compositions of various constituents pursued by the formulation of a numerical model considering various elements such as magnetic field strength, magnetic particle size and MR fluid yield strength. Using a commercial software, COMSOL, a magnetically energized circuit is examined to obtain the details regarding the number of turns, current supply and strength of the magnetic field at predefined points, and a simulation study is carried out. Successively, the developed and optimized MR fluid is introduced between the gap of the fixed plate and rotating disk under the influence of the magnetic field over the fluid territory. A full-fledged test rig setup for the MR brake system is established, and an experimental study is carried out focusing on the shaft speed and braking torque developed during the braking process. The results are also plotted for various current input values. The current input value ranges from 0 to 2 amp, and the respective torque value is obtained. Likewise, the performance of the torque by the proposed MR brake system used simulated results in a derived theoretical model, and a comparative study is carried out with the experimented results.

Magnetorheological fluids: synthesis, properties and applications

“…The additives give the system properties such as good adhesion, particularly to particles, anti-corrosive effect and stability at high temperature (~ 150 oC). Additionally, high viscosity additives such as fat or other thixotropic materials are added to the base fluid to improve the stability of the particles against sedimentation [4], [20].…”

“…A wide range of materials can be used for FMR stabilisation effects, e.g. Jinaga et al [20] implemented lithium grease as a stabiliser for mixtures of silicone oil, iron carbonyl particles and the commercial additive Triton X-100, finding a clear influence on viscosity and sedimentation rate [20]. Mesquida and Lässing [15] studied the effect of two surfactant additives, the sodium acid dodecylbenzene sulfate salt and versamul (in solution state), obtaining better performance with versamul in terms of viscosity and sedimentation.…”

The Synthesis of Organic Oils Blended Magnetorheological Fluids with the Field-Dependent Material Characterization

“…In addition, the material of the magnetic particles plays an essential role in attaining maximum yield stress, as it is proportional to the square of saturation magnetization of magnetic particles [12,13]. The literature shows the yield stress value varies with respect to applied magnetic field and shows a nonlinear increment with the increasing volume fraction of particles [5,14,15]. Lord MRF 132DG possesses a yield strength of 48 KPa subjected to 288 kA/m [11].…”

From Brush to Dendritic Structure: Tool for Tunable Interfacial Compatibility between the Iron-Based Particles and Silicone Oil in Magnetorheological Fluids

“…When a magnetic field is applied, the dispersed particles create a chain-like structure along the lines of the magnetic field direction, which causes an increase in apparent viscosity of several orders of magnitude. In this situation, MR fluid can be considered as Bingham plastic material. , The remarkable rheological changes, including a transition from a liquid-like state to a solid-like state, occur within microseconds and are reversible. , The great controllability of the yield stress as a measure of the internal structure rigidity of MR fluids, dependent on the magnetic field strength, can be utilized in vibration control , but also in many other applications, e.g., brakes, , clutches, , dynamometers, aircraft landing gears, and helicopter lag dampers …”