What does Magnet Grade mean?
What is Magnet Grade?
Often you will see that magnet names are a combination of letters and numbers like N42, N42SH, N35UH. The following gives an introduction to what that means.
The numbers
The numbers refer to how much work a magnet can do in relation to its volume/size. The higher the number, the more energy (Maximum Energy Product, MGOe) the magnet can generate, and the more force the magnet can exert on objects around it. For example, a magnet with a 40 grade is less powerful than one with a grading of 52. Even though they are the exact same size. At the current time, the weakest Neodymium magnets have a grade of 35, while the most powerful ones go up to 52. A typical magnet has a grade of 40 or 42 as this is where you find the best relationship between price and performance.
The letters
As we now know the magnet grade is a number. Very often the number has one a more letters on each side. The number on the left side is “N” for Neodymium. The letters on the right side refer to the Max Operating Temperature and the Curie Temperature. Examples are N42, N42SH, N35UH and so on.
How is Magnet Grade Calculated?
Since magnet grade can be used to denote how much electricity the magnet can induce in a coil, magnet grade is often measured using a flux meter in order to determine precisely how much electron flow is generated in the coil when the magnet is present. The greater the change (or magnetic flux), the higher the magnet grade will be on the magnet.
Why Should I Know About This Before Buying a Magnet?
No matter whether you are purchasing Neodymium magnets for a power generating system or for exerting force on an object, knowing the strength of the magnet is very important. If you buy a magnet that is too strong (the magnet grade is too high), it can ruin any system that you put it in. On the other hand if the magnet grade is too low, the system may not work at all, or not perform as expected. For daily use the most important thing to remember about magnet grade is that a high number means a more powerful magnet and that the letters following the numbers refer to the heat resistance of the magnet.
Also have in mind that other things influence the strength of a magnet. Those are:
- The shape and proportions of the magnet
- The volume of the magnet
- Surrounding materials: Is the magnet encapsulated in a metal cape, quality of the metal to which the magnet is attached
Magnet grade is a theoretical value that can be difficult to grasp and apply to real life projects. For that reason we also test each of our magnets to see how many kilos they can carry when attached to a metal plate. Often this is the value you need, as it tells how much weight a magnet supports before loosing grip. You can find this information on each product page.