Adsorption force

Adsorption force, which is also called attraction, defines the force working between two objects such as a magnet and a magnetic body containing iron. Newtons (N) are used as the representative unit for adsorption force. Basic units of mass such as kilogram-force (kgf) and pound-force (lbf) may also be used.

Load

Load is defined as a force produced where two points are in contact such as between a magnet and a steel plate. This the load from this force is changed depending upon friction, the state of the surface, and an impact. A slip load which indicates whether a magnet and a steel plate and the like can stay in place without slipping while withstanding a load applied horizontally, is also denoted in units of Newtons (N).

Method for measuring adsorption force and slip load

The resulting numerical values tend to vary according to the usage environment and the measurement method. As a result, it is necessary to define the usage environment and the measurement method when using adsorption force in the specification of a magnet. At Magfine, these forces are defined when measured under the following measurement method and usage conditions.

Measurement method

• 1.Adsorption force
  Adsorption force is the force when a magnet is pulled away from a steel plate perpendicular to the vertical axis and the magnet separates from the steel plate.
  
• 2.Slip load
  A slip load is the force when a magnet is pulled parallel to the horizontal axis and the magnet moves away from the steel plate.
  

Environment conditions

• 1.The thickness (T) of the steel plate and the thickness of the magnet (H) are as stated above.
• 2.The magnet is placed in the center of the steel plate.
• 3.The surface area of the steel plate is at least three times greater (300%) than the surface area of the magnet.
• 4.The material of the steel plate is pure iron (Fe).
• 5.The surface of the steel plate is flat without unevenness and the coefficient of friction is not considered.
• 6.Any gap between the steel plate and the magnet is closed so that there is no gap.