磁気再構成可能な濡れ性・接着性カップリングによる適応潤滑
Xinrui Li1, Xiaoqiang Fan1, Yihan Zhang1
1Key Laboratory of Advanced Technologies of Materials, Ministry of Education, Southwest Jiaotong University, Chengdu, P. R. China.
Abstract:
Reversible and synchronized regulation of wettability and adhesion remains elusive in adaptive lubrication, where structural rigidity and chemical fixation constrain interfacial responsiveness to external fields. In this study, we introduce a magnetically reconfigurable lubrication strategy that integrates magneto-responsive lubricants with oleophobic surfaces to achieve field-driven modulation of wettability, adhesion, and friction. Under magnetic actuation, nanoparticles assemble into chain-like anisotropic structures, generating directional magnetic forces that compete with surface tension to reconfigure droplet morphology. The balance of these forces, defined by the magnetic Bond number, governs the wetting transition, as reflected by a reduction of the apparent contact angle from 153° to 114° and nearly threefold expansion of the wetted area. Enhanced interfacial pinning expands hysteresis from 5° to 42°, enabling reversible droplet manipulation. Meanwhile, field-induced nanoparticle aggregation at the solid-liquid interface generates vertical magnetic gradients and localized negative pressures below -100 kPa, yielding reversible adhesion up to 12 N. These coupled effects enable magnetic tuning of interfacial friction, with the coefficient varying from 0.15 to 0.55 and torque from 0.005 to 0.10 N·m. This work establishes a quantitative, field-driven framework for magnetically regulated interfacial control, enabling adaptive lubrication in applications such as robotic joints, adaptive bearings, and precision motion systems.
関連する概念動画
Surface Tension, Capillary Action, and Viscosity
The various IMFs between identical molecules of a substance are examples of cohesive forces. The molecules within a liquid are surrounded by other molecules and are attracted equally in all directions by the cohesive forces within the liquid. However, the molecules on the surface of a liquid are attracted only by about one-half as many molecules. Because of the unbalanced molecular attractions on the surface molecules, liquids contract to form a shape that minimizes the number...
Magnetic Susceptibility and Permeability
When diamagnetic materials are placed under an external magnetic field, the moments opposite to the field are induced. Hence, the susceptibility for diamagnets has a minimal negative value of 10-5–10-6. Since...
Magnetic Damping
If, however, the bob is a slotted metal plate, the magnet produces a much smaller effect. When a slotted metal plate enters the field, an emf is induced by the change in flux; however, it is less effective because the slots limit the...
Characteristics of Dry Friction
Before the wheelbarrow starts moving, the static frictional force acts tangentially to the contact surface, opposing the force that is about to induce the motion. This frictional force prevents the...
Micelles


