Magnets come in different shapes and sizes, and when shopping for neodymium magnets, you may come across the term “grade,” which refers to the strength of the magnetic material used in the magnet. Understanding the grades of magnets can help you choose the right one for your specific application.

What Are Magnet Grades?

Magnet grades are a measurement of the magnetic strength of the magnet, which is indicated by a capital N followed by a two-digit number and sometimes extra letters. The N stands for Neo, which is short for neodymium, one of the four types of magnets commercially available. The number after the N indicates the maximum energy product in MGOe, which is the maximum strength of the magnetic material. The higher the number, the stronger the magnet. But, there is a range for each grade of neodymium magnet.

N45 vs N52

For example, the final energy product for an N45 magnet can range from 43-46 MGOe. N52 range from 49-52 MGOe. That is why an N52 magnet must be stronger than an N44 magnet of the same size and shape. Because the N52 neodymium magnet has greater magnetic strength than the N45 magnet.

N50 vs N52

N50 must not be stronger than N52. Because the range of N50 is 47-51 MGOe. There are some ranges that are the same as N52.

How Do Magnet Grades Affect Magnet Strength?

The strength of a magnet depends on several factors, including its size, shape, and the magnetic material used. Although the grade is an important factor, it’s not the only factor that determines the strength of a magnet. For instance, two magnets of the same size and shape but with different grades may have a strength difference of anywhere between 11-21% or even lower. As a practical rule of thumb, there’s 1% more pull force for every extra MGOe. So, an N52 magnet is about 7% stronger than an N45 magnet of the same size and shape. ( The pull force of  big size N45  is bigger than the small size N52 magnet.)

Do all kind magnets use the same grade system?

No, the grades of ferrite, SmCo, and neodymium magnets are not the same. Each type of magnet has its own grading system based on its magnetic properties such as strength, maximum energy product, coercivity, and temperature stability.
For example, neodymium magnets are graded based on their maximum energy product (BHmax) which is a measure of their magnetic strength. The higher the grade (such as N52), the stronger the magnet. SmCo magnets are graded based on their maximum energy product and temperature stability, while ferrite magnets are graded based on their magnetic flux density and coercivity.
Therefore, it’s important to choose the appropriate magnet type and grade based on the specific application requirements.

Extra Letters On Neodymium Magnet Grades

Sometimes, magnet grades have extra letters at the end of the grading, which indicate how well the magnet can withstand high temperatures. The standard neodymium magnets can generally withstand temperatures up to 80°C. If heated above this, they will lose some of their magnetic strength even after being cooled down. In contrast, neodymium magnets with extra letters can withstand higher temperatures, up to 150°C, for instance. However, they are generally weaker and more expensive.

Conculsion

The grade of a magnet is a crucial factor in determining its strength, but it’s not the only factor. When shopping for magnets, it’s important to consider the size, shape, and magnetic material used, in addition to the grade. Neodymium magnets are generally stronger than ferrite magnets and come in different grades, each with its own maximum energy product. Additionally, the extra letters at the end of the grading indicate how well the magnet can withstand high temperatures. By understanding the grades of magnets, you can make an informed decision on which magnet to choose for your specific application.