Displacement force: Move the adhesive force to another level

The displacement force describes the force required to displace a magnet parallel to a surface to which it adheres. It is an important parameter when using magnets, especially when they are used on smooth or rough surfaces.

How is the displacement force generated?

The displacement force is a combination of the **adhesive force** of the magnet and the **frictional forces** that act between the magnet and the surface. The force required varies considerably depending on the material, surface properties and magnet type. While the adhesive force acts perpendicular to the surface, the displacement force acts on the adhesive force and also overcomes the frictional forces.

Factors that influence the displacement force

The displacement force depends on several factors:

• Surface properties: Smooth surfaces lead to lower friction and therefore lower displacement force, while rough surfaces increase friction.
• Magnet strength: A stronger magnet generates a higher adhesive force, which also increases the sliding force.
• Surface material: Ferromagnetic materials increase the adhesive force, while other materials can reduce it.
• Additional forces: Lubricants or coatings can reduce friction and thus lower the sliding force.

Mathematical description of the displacement force

The displacement force can be calculated approximately by:

F_displacement = F_haft × μ

Where:

• F_displacement: Displacement force (in Newtons)
• F_sticky: Adhesive force of the magnet (in Newtons)
• μ: Coefficient of friction between magnet and surface

Applications of the displacement force

The displacement force is an important parameter in many areas:

• Industrial fasteners: For magnets that hold workpieces or tools, the displacement force is crucial for stability.
• Magnetic holders: Magnetic holders for tools, boards or displays must be designed so that the displacement force is sufficiently high to prevent slipping.
• Transport systems: Magnetic grippers in automation processes require precise control of the displacement force in order to move workpieces safely.
• Attachment systems in vehicles: For magnetic attachments in vehicles, e.g. for sensors, the displacement force is a decisive factor for reliability.

Difference between holding force and displacement force

While the holding force describes the vertical attractive force of a magnet, the displacement force is a combination of holding force and friction. In practice, the displacement force is usually lower than the holding force, as it depends on the friction between the magnet and the surface.

Interesting facts about displacement force

Did you know that the displacement force is often more important than the pure holding force in harsh environments? For example, magnets used in tool mountings or conveyor belts must not only adhere strongly, but also withstand movement or vibrations. This is why special coatings or surface structures are often used to specifically increase friction and thus the displacement force.