Strength is the term we use to describe how powerful a magnet is. On other websites, you may see similar words used, such as "bearing capacity" or "holding power". By Strength, we mean the number of kilograms it takes to pull the magnet vertically from a steel plate. This can be illustrated with this graphic:
In the graphic, we see the three forces at play. Strength (a) is the number of kg needed to vertically remove the magnet from the metalplate. This is a common way to describe the strength of a magnet.
The next is Frictional Force (b), which can be higher or lower than Strength. That's because Frictional Force depends on the surface of the metal plate and magnet. For example, our rubber magnets provide high friction, while magnets that have a smooth nickel surface have low friction.
The final force is Holding Power (c), which is a combination of Strength and Frictional Force. Holding Power depends mainly on the angle of the object to be held, as this determines the influence of the friction force.
Strength (a) is the same as previously described.
Carrying Capacity (b) is determined by the Strength, but also by the Frictional Force. As a rule of thumb, the Carrying Capacity of a standard nickel-plated neodymium magnet is approximately 15% of the magnet's Strength. More than 15% and the magnet will slide down. If the magnet has a strength of 10 kg, then the Carrying Capacity is approximately 1.5 kg. Rubberized magnets will have a higher Carrying Capacity due to their higher friction.
Summarization
- At Brisingi, we inform you of the Strength of a magnet, which is the number of kg required to pull the magnet vertically from a steel plate.
- Holding Power depends on Strength + Frictional force + the angle of the object to be held up.
- Frictional force is mainly determined by the surface of the magnet and the metal plate. Rubber, for example, has a higher friction than nickel.
- Carrying Capacity is mainly determined by Strength + Friction. As a rule of thumb, a standard nickel-plated neodymium magnet can hold approximately 15% of its Strength. Rubber magnets can hold more due to their higher friction.