Magnetorheological Fluid

Indicator translation: 

1) Sedimentation stability: This refers to the difficulty of solid particles precipitating over a certain period in a magnetorheological fluid. The lower the sedimentation ratio, the higher the sedimentation stability, resulting in less external interference during product use. Additional explanation: Among the many factors that lead to particle sedimentation, three main components are primarily involved: magnetic particles, carrier liquid (base oil), and additives (surfactants). Therefore, much work has been conducted to enhance the sedimentation stability of magnetorheological fluids (MRFs) using these three methods. During the particle modification phase, factors such as weight concentration, size distribution, particle shape, coating materials, and combinations of different sized particles have been proposed. For the modification of the carrier liquid, increases in density, control of wettability, and the use of natural oils, lubricants, greases, and ethyl acetate and butyl acetate oils have already begun. Recently, in certain formulations aimed at improving sedimentation stability, some additives like aluminum stearate have been utilized to enhance the redisperability of agglomerated particles. Furthermore, efforts are actively underway to modify particles and base oils using more than two formulations to achieve higher sedimentation stability. These are challenging tasks in the exploration and development of successful application systems for MRFs. 

2) Shear Yield Stress: The greater the upper limit of the yield stress of a magnetorheological fluid, the larger the adjustable range of the magnetorheological device, enabling broader applications. The shear yield stress of the magnetorheological fluid also represents its curing strength; a higher shear yield stress parameter indicates a finer microstructure, resulting in better strength, plasticity, and durability of the material. Other notes: Shear yield stress refers to the maximum shear stress at which material experiences shear deformation under loading at a specific force level or when it can no longer sustain an increase in loading intensity. In other words, when the material is subjected to a certain shear force, its strength no longer increases, and actual shear deformation occurs. This is where the applied shear force is expressed as shear stress; shear stress is defined as shear yield stress. Shear stress is the interaction force that arises at any cross-section (shear plane) within an object when it deforms due to external factors (load, temperature changes, etc.). The concentration of internal force, or the internal force per unit area, is called "stress." Stress can be decomposed into components perpendicular to the cross-section (shear plane), known as "normal stress" or "normal stress," and components tangential to the cross-section (shear plane), referred to as "shear stress." 

3) Response Time: Utilizing electromagnetic reactions, it can respond to road conditions within milliseconds, suppress vibrations, and maintain vehicle stability, especially when encountering obstacles at high speeds, showcasing its advantages. Its response speed is five times faster than traditional suspensions, ensuring smooth vehicle operation even on the roughest surfaces. 

4) Density: The lower the density of solid matter, the lighter the weight. 

5) Zero-field viscosity: When no external magnetic field is applied to the magnetorheological fluid, it is considered to exhibit typical Newtonian fluid behavior, and the viscosity displayed at this time is referred to as zero-field viscosity. Typically, the zero-field viscosity increases with the increase of the volume fraction of soft magnetic particles. The increase in zero-field viscosity can also lead to a reduction in the adjustable stress range of the magnetorheological fluid, thereby limiting its application in high-precision and high-demand fields. Therefore, it is considered better for the zero-field viscosity of the magnetorheological fluid to be lower, provided that it can meet the required specifications.