What are the grades of NdFeB magnets？

NdFeB magnets, also known as neodymium magnets, are the strongest permanent magnets commercially available today. Because of their exceptional magnetic strength and compact size, NdFeB magnets are widely used in industries such as electronics, automotive, renewable energy, medical devices, and industrial automation.

However, not all NdFeB magnets are the same. They are classified into different grades, and understanding these grades is essential for selecting the right magnet for your application. In this article, we’ll explore what NdFeB magnet grades mean, how they are categorized, and how to choose the correct one.

What Does the Grade of NdFeB Magnets Mean?

The grade of NdFeB magnets primarily indicates their maximum energy product, measured in Mega Gauss Oersteds (MGOe). This value reflects how much magnetic energy the magnet can store. In general:

Higher grade = stronger magnetic force

Lower grade = less magnetic force

For example, an N52 magnet is stronger than an N35 magnet of the same size.

Common NdFeB Magnet Grade Designations

NdFeB magnets are typically labeled with a combination of numbers and letters, such as N35, N42, or N52H. Each part of the designation has a specific meaning.

1. The “N” Number (Magnetic Strength)

The number following the “N” represents the maximum energy product:

N35 – Standard strength, cost-effective

N42 – Higher magnetic performance

N48 – Very strong magnetic force

N52 – One of the strongest commercially available grades

Higher N-numbers provide stronger magnetic fields but may be more sensitive to temperature.

2. Temperature Resistance Letters

Some NdFeB magnets include an additional letter that indicates their maximum operating temperature:

Letter：N

Max Working Temperature：80°C (176°F)

Letter：M

Max Working Temperature：100°C (212°F)

Letter：H

Max Working Temperature：120°C (248°F)

Letter：SH

Max Working Temperature：150°C (302°F)

Letter：UH

Max Working Temperature：180°C (356°F)

Letter：EH

Max Working Temperature：200°C (392°F)

For example:

N42H offers high magnetic strength with improved heat resistance.

N35SH is suitable for environments with elevated temperatures.

Most Popular Grades of NdFeB Magnets

Here are some commonly used grades and their typical applications:

N35: Consumer products, toys, basic holding applications

N42: Motors, sensors, speakers

N48: Industrial equipment, generators

N52: High-performance motors, aerospace, precision devices

N35H / N42SH: Automotive and industrial applications exposed to heat

Choosing the correct grade ensures optimal performance and longer service life.

How to Choose the Right Grade of NdFeB Magnets

When selecting NdFeB magnets, consider the following factors:

Required magnetic strength

Operating temperature

Working environment (humidity, corrosion, vibration)

Cost and availability

Magnet size and shape constraints

A higher grade is not always better—using an overly strong magnet can increase costs without real benefits.

Conclusion

Understanding the grades of NdFeB magnets is crucial for making the right choice in both industrial and commercial applications. From standard N35 magnets to high-temperature grades like SH and UH, each type of NdFeB magnets is designed to meet specific performance requirements.

By carefully evaluating magnetic strength, temperature resistance, and application conditions, you can select the ideal NdFeB magnet grade that delivers reliability, efficiency, and long-term value.