For neodymium magnets, there will be different grades of neodymium magnets, and choosing the correct grade of neodymium is crucial. It even determines the success or failure of your project. If you want to choose the right grade, you can consult professional magnet manufacturers, such as CORT MAGNETS. Meanwhile, you can check out some blog introductions or knowledge web pages about magnets on their official website
CORT MAGNETS, as a professional magnet manufacturer, is committed to providing customers with one-stop solutions for magnets. To help our customers have a better understanding of neodymium magnet products or other magnets, we have created the TECHNICAL INFO webpage. It includes the Magnet Performance Table, Magnet Plating Requirement, and Magnet Size Range of NdFeB, SmCo, Alnico, and Ferrite to better help customers understand Magnets. Choose the best cost performance. If you have any questions, you can contact us at any time for help!
Neodymium magnet grades define a magnet’s strength and, in some cases, its temperature resistance. Manufacturers classify these magnets using a letter-number system that reflects their maximum energy product and temperature tolerance. For example, grades like N35 or N52 indicate magnetic strength, while suffixes such as “SH”, “S”, “M”, and “EH” show higher temperature ratings. Selecting the correct grade ensures reliable performance in demanding environments, as shown in the table below:
Grade | Max Energy Product (MGOe) | Temp Rating (°C) |
|---|---|---|
N35 | 33-36 | ≤80 |
N35M | 33-36 | ≤100 |
N42SH | 40-43 | ≤150 |
Table of Contents
Key Takeaways
Neodymium magnet grades show a magnet’s strength and temperature resistance using a letter-number system like N35 or N52.
The number after ‘N’ indicates the magnet’s maximum energy product (MGOe), with higher numbers meaning stronger magnets.
Suffix letters such as M, H, SH, UH, and EH represent the magnet’s ability to resist heat and maintain strength at higher temperatures.
Higher-grade magnets like N52 offer more strength but can be more expensive and sensitive to heat than lower grades like N35.
Choosing the right magnet grade depends on your project’s strength needs, temperature conditions, and budget.
Magnets with higher temperature suffixes perform better in hot environments but may cost more and sometimes have less strength at room temperature.
Neodymium magnets keep their strength well over time if used within their temperature limits and handled carefully.
Always match the magnet grade and suffix to your specific application to ensure safety, reliability, and cost efficiency.
Neodymium Magnet Grades
Grade Meaning
Neodymium magnet grades provide a standardized way to describe the strength and performance of neodymium magnets. The grade reflects the magnet’s maximum energy product, also known as (BH)max, which measures how much magnetic energy the magnet can store. This value, measured in Mega-Gauss-Oersteds (MGOe), directly relates to the magnet’s strength and holding power.
The number following the letter ‘N’ in the grade (such as N35 or N52) indicates the (BH)max value. A higher number means a stronger magnet.
For example, an N35 magnet has a maximum energy product of 35 MGOe, while an N52 magnet reaches 52 MGOe. This difference means an N52 magnet can generate a stronger magnetic field and hold more weight than an N35 magnet of the same size.
Suffix letters, such as M, H, SH, UH, and EH, indicate the magnet’s temperature resistance. These suffixes specify the highest temperature at which the magnet can operate without losing its magnetic properties.
Neodymium magnet grades also influence other magnetic properties, such as remanence (the magnet’s ability to retain magnetization) and coercivity (resistance to demagnetization). These factors play a crucial role in industrial and consumer applications, where reliability and performance matter.
Tip: Selecting the right grade ensures the magnet performs well in its intended environment, whether in electronics, motors, or specialized equipment.
'N' Prefix
The ‘N’ prefix in neodymium magnet grades stands for “neodymium,” identifying the magnet as part of the neodymium-iron-boron (NdFeB) family. This prefix is always followed by a number that represents the magnet’s maximum energy product. Suffix letters may follow to indicate temperature resistance.
Component | Meaning |
|---|---|
N | Indicates a neodymium-based magnet |
Number (e.g., 35, 42, 52) | Represents the maximum energy product (BH)max in MGOe, indicating magnetic strength |
Suffix letter (e.g., H, SH, UH) | Denotes maximum operating temperature or temperature tolerance |
This grading system helps users quickly identify the magnet’s core material, strength, and temperature capabilities. For example, N42SH means a neodymium magnet with a strength of 42 MGOe and super-high temperature resistance.
Grade Number Range
Manufacturers produce neodymium magnet grades across a range of strengths to suit different applications. The typical range starts at N30 or N35 and extends up to N55. Most commonly available grades include N35, N42, N48, N52, and N56. Higher numbers indicate stronger magnets, but they also come with higher costs and sometimes increased sensitivity to heat.
Magnet Grade | Maximum Energy Product (MGOe) | Notes |
|---|---|---|
N35 | 33 – 36 | Most common grade, typical starting point |
N52 | 49-53 | One of the strongest standard grades |
N56 | 52-56 | Strongest standard neodymium magnet grade |
Laboratory measurements confirm that higher-grade magnets deliver greater pull force and magnetic flux density. For example, an N52 magnet can achieve the same lifting force as an N35 magnet but with a smaller size or fewer magnets. This makes higher grades ideal for compact, high-performance applications.
N35 magnets suit cost-sensitive projects and general use, such as crafts or refrigerator magnets.
N52 magnets are preferred for high-tech equipment, motors, and applications where maximum strength in a small space is critical.
Neodymium magnet grades allow engineers and designers to match the right magnet to the demands of each project, balancing strength, size, cost, and temperature resistance.
Grading System
Maximum Energy Product
The neodymium magnet grading system relies on scientific measurements to define each grade. The most important measurement is the maximum energy product, often abbreviated as (BH)max. This value shows how much magnetic energy a magnet can store and deliver. Manufacturers express (BH)max in Mega Gauss Oersteds (MGOe), and the grade number directly matches this value. For example, an N35 magnet has a (BH)max of about 35 MGOe, while an N52 magnet reaches 52 MGOe.
The process of determining (BH)max involves plotting the BH Curve, which shows the relationship between magnetic field strength (H) and magnetic flux density (B). The highest point on this curve, where the product of B and H is greatest, gives the maximum energy product. Other key measurements include residual induction (Br), which shows how much magnetism remains after removing the magnetizing force, and coercive force (Hc), which measures resistance to demagnetization.
Grade | Residual Induction (Br) | Coercive Force (Hc) | Maximum Energy Product (BHmax) |
|---|---|---|---|
N35 | 11.7–12.2 kGs | ≥10.9 kOe | 33–36 MGOe |
N38 | 12.2–12.6 kGs | ≥11.3 kOe | 36–39 MGOe |
This table demonstrates that the grade number closely matches the (BH)max value. The grading system allows engineers to compare magnets based on standardized, quantifiable properties such as magnetic flux density and pull force. As a result, users can select the right magnet for their needs with confidence.
Note: The grading system provides a reliable way to match magnet strength to application requirements, making it easier to design efficient products.
Suffix Letters
1.Common Suffixes
Neodymium magnet grades often include suffix letters after the grade number. These suffixes—such as M, H, SH, UH, and EH—refer to the magnet’s intrinsic coercivity (Hci). Intrinsic coercivity measures how well a magnet resists becoming demagnetized, especially at higher temperatures. A higher Hci means the magnet can withstand more heat before losing its magnetic properties.
Common suffixes include:
M: Medium temperature resistance
H: High temperature resistance
SH: Super high temperature resistance
UH: Ultra high temperature resistance
EH: Extra high temperature resistance
2.Temperature Resistance
Suffix letters serve as indicators of a magnet’s temperature tolerance. They do not set absolute temperature limits but provide guide values based on intrinsic coercivity. For example, an N42SH magnet can operate at higher temperatures than a standard N42 magnet. However, the actual temperature performance depends on factors such as the magnet’s size, shape, and the surrounding magnetic circuit.
The suffix system helps users quickly identify which magnets will perform reliably in hot environments. Engineers must still consider the full design and application context to ensure the magnet will not lose strength during use.
Tip: Always check both the grade number and suffix when selecting a magnet for high-temperature applications. The right combination ensures lasting performance and safety.
Magnet Strength
Grade Comparison
Neodymium magnets come in a range of grades, each offering a different level of magnetic strength. Engineers and manufacturers rely on these grades to select the right magnet for each application. Grades such as N35, N42, and N52 represent some of the most common options. The grade number directly relates to the magnet’s maximum energy product (MGOe), which measures the amount of magnetic energy stored within the magnet. Higher grade numbers indicate stronger magnets.
Industry benchmarks confirm that the maximum energy product serves as the primary standard for comparing magnet strength. For example, N35 magnets offer a maximum energy product of about 35 MGOe, while N52 magnets reach up to 52 MGOe. This grading system allows users to match magnet strength to specific requirements, whether for electronics, motors, or industrial tools.
Comparative tests provide further validation of these differences. Pull force tests measure the force required to detach a magnet from a steel surface, giving a direct and repeatable measure of magnetic strength. Gaussmeter measurements assess the magnetic field strength near the magnet, expressed in Gauss or Tesla. These tests consistently show that higher-grade magnets, such as N52, produce stronger magnetic fields and greater pull force than lower grades like N35 or N42. Experimental setups, including side-by-side or stacked magnet arrangements, reveal that magnet grade and configuration both influence overall strength.
Researchers have also used advanced tools, such as iOLab devices, to measure magnetic dipole moments and forces between magnets. These experiments involve levitating or repelling magnets, recording distances and forces, and calculating magnetic moments. The results reinforce the values found in magnet strength tables and confirm the reliability of the grading system.
Note: The strength of a neodymium magnet depends not only on its grade but also on its size, shape, and arrangement. Always consider these factors when selecting a magnet for a specific task.
Strength Table
The following table summarizes the relative strength of common neodymium magnet grades. Each grade’s maximum energy product (MGOe) reflects its intrinsic magnetic strength.
Magnet Grade | Maximum Energy Product (MGOe) | Typical Pull Force (kg, 1″ cube) |
|---|---|---|
N35 | 33 – 36 | ~10 |
N42 | 40 – 46 | ~12 |
N48 | 46 – 49 | ~14 |
N52 | 50 – 53 | ~16 |
Experimental data support these values. For instance, computer programs record magnetic field strength at various distances, producing graphs that show how field strength decreases as distance increases. Practical experiments, such as measuring the mass of iron attracted by different magnets at various temperatures, further validate these numbers. At 0°C, a neodymium magnet attracted 405 grams of iron, while other materials attracted much less, highlighting the superior strength of neodymium.
Industry standards and repeated laboratory tests ensure that these strength values remain consistent and reliable. By consulting the strength table, engineers and designers can quickly identify the best magnet grade for their needs, balancing strength, size, and cost for optimal performance.
Temperature Ratings
Suffix Meaning
Suffix letters in neodymium magnet grades play a crucial role in identifying a magnet’s temperature resistance. These letters—such as M, H, SH, UH, and EH—signal the maximum temperature at which a magnet can operate without suffering irreversible loss of magnetic strength. For example, a magnet labeled N42SH can withstand higher temperatures than a standard N42 magnet. Manufacturers assign these suffixes based on the magnet’s intrinsic coercivity, which measures its ability to resist demagnetization at elevated temperatures.
M stands for Medium temperature resistance.
H means High temperature resistance.
SH indicates Super High temperature resistance.
UH refers to Ultra High temperature resistance.
EH represents Extra High temperature resistance.
These suffixes help engineers and designers quickly identify which magnets will perform reliably in environments with elevated heat. Practical testing and manufacturer data confirm that standard neodymium magnets typically operate up to 80°C, while high-grade variants with suffixes can tolerate temperatures from 100°C to 230°C. Magnet shape also affects temperature tolerance. Thin or flat magnets may lose strength at lower temperatures, while those with a diameter-to-height ratio less than 4 maintain magnetism even above their rated temperatures.
Tip: Always check both the grade number and suffix when selecting magnets for high-temperature applications. This ensures the magnet will maintain its strength and reliability.
Temperature Table
The following table summarizes common neodymium magnet grades and their maximum operating temperatures. These values reflect both manufacturer specifications and results from practical experiments:
Grade | Suffix | Max Operating Temp (°C) | Max Operating Temp (°F) |
|---|---|---|---|
N35 | None | 80 | 176 |
N35M | M | 100 | 212 |
N35H | H | 120 | 248 |
N35SH | SH | 150 | 302 |
N35UH | UH | 180 | 356 |
N35EH | EH | 200 | 392 |
Empirical studies validate these temperature ratings. For instance, BH curve measurements at different temperatures show that neodymium magnets experience reversible and irreversible losses in magnetic strength. Temperature cycling experiments reveal that magnets retain their properties if kept below their maximum operating temperature. Comparative testing also highlights that higher-grade neodymium magnets, such as N52, may have lower maximum operating temperatures than lower grades like N42, emphasizing the importance of matching grade and suffix to the application.
Statistical analyses, including the use of the Weibull distribution and Maximum Likelihood estimation, confirm the reliability of these temperature ratings. The analysis demonstrates that as temperature increases, the likelihood of magnet failure rises, and the average time between outages decreases. This robust statistical framework supports the temperature thresholds listed in the table, giving engineers confidence in selecting the right magnet for demanding environments.
Neodymium magnets increase in strength at low temperatures, down to about -125°C, and retain significant magnetism even near -196°C. However, exceeding the maximum operating temperature can cause permanent loss of strength.
Choosing a Grade
Application Needs
Selecting the right magnet starts with a clear understanding of the application’s requirements. Engineers and designers must consider factors such as the environment, expected temperatures, space constraints, and required magnetic strength. Industry guidelines recommend matching the magnet’s maximum energy product and temperature resistance to the highest and lowest temperatures expected in the application. Environmental factors like moisture, chemicals, and dust also influence magnet performance and lifespan. Protective coatings, such as nickel or epoxy, help prevent corrosion in harsh environments. Safety remains a priority, so proper handling and storage are essential, especially for high-strength magnets.
Tip: Always analyze the operating conditions and performance needs before choosing a magnet grade. This approach ensures reliability and safety.
Strength vs. Temperature
When comparing magnet grades, users must balance magnetic strength with temperature stability. The following table highlights key trade-offs between neodymium and ceramic magnets:
Metric | Neodymium Magnets (Typical Range) | Ceramic Magnets (Typical Range) | Unit | Significance |
|---|---|---|---|---|
Maximum Energy Product | 30 – 55 | 1 – 5 | MGOe | Magnetic strength/energy density |
Residual Magnetic Field | 11,000 – 14,800 | 2,000 – 4,500 | Gauss (G) | Field strength after magnetization |
Coercivity | 10,000 – 14,000 | 2,000 – 4,000 | Oersteds | Resistance to demagnetization |
Intrinsic Coercivity | 12,000 – 35,000+ | 2,000 – 4,500 | Oersteds | Heat resistance to self-demagnetization |
Neodymium magnet grades offer high magnetic strength but lower maximum operating temperatures. Standard grades operate up to 80°C, while suffix grades like SH, UH, and EH can reach 150°C, 180°C, or even 200°C. Higher temperature grades often cost more and may sacrifice some strength. Designers must weigh these trade-offs to ensure the magnet performs reliably in its intended environment.
Use Cases
Industry case studies and guidelines provide practical examples of how to choose the right magnet grade:
High-performance headphones use neodymium magnets for their strong magnetic fields and lightweight properties. This choice results in improved sound quality and durability.
Aircraft control systems often require samarium-cobalt magnets due to their superior temperature stability and resistance to demagnetization, ensuring safety under extreme conditions.
Motors and generators benefit from high-coercivity neodymium magnets, which resist demagnetization during operation.
Medical devices often use corrosion-resistant magnets, such as coated neodymium or samarium-cobalt, to ensure safety and longevity.
For environments above 80°C, high-temperature grades like N42SH or N48H are recommended to prevent permanent loss of magnet strength.
Cost-effective ferrite magnets suit general electronics, while neodymium magnet grades like N35 or N42 fit applications needing strong pull force at room temperature.
Note: Always select a magnet grade that meets or exceeds the application’s temperature and strength requirements. Consider protective coatings and budget constraints for optimal performance and durability.
Common Misconceptions
Higher Grade Myths
Many people believe that a higher neodymium magnet grade always means a better magnet. This idea often leads to unnecessary costs or performance issues. Higher grades, such as N52 or N55, offer stronger magnetic fields. However, these magnets can be more brittle and sensitive to heat. In some applications, a lower grade like N35 or N42 works better because it provides enough strength and greater stability.
Note: The strongest magnet is not always the best choice. Engineers select grades based on the specific needs of each project, not just maximum strength.
A higher grade may also require more careful handling. Stronger magnets can pinch fingers or damage nearby electronics. For many everyday uses, such as crafts or simple closures, a mid-range grade offers a safer and more cost-effective solution.
Suffix Confusion
Suffix letters in magnet grades often confuse. Many users think the suffix only affects temperature resistance, but it also relates to the magnet’s ability to resist demagnetization. For example, the “SH” in N42SH means “Super High” temperature resistance, but it also signals higher intrinsic coercivity.
Suffix | Meaning | Max Temp (°C) | Intrinsic Coercivity (kOe) |
|---|---|---|---|
None | Standard | 80 | ≥12 |
H | High | 120 | ≥17 |
SH | Super High | 150 | ≥20 |
UH | Ultra High | 180 | ≥25 |
EH | Extra High | 200 | ≥30 |
Some users select a magnet with a high suffix, expecting it to work better in all conditions. In reality, suffixes only improve performance at higher temperatures. At room temperature, a standard grade without a suffix often performs just as well.
Application Fit
Selecting the right magnet grade requires more than just picking the highest number or the most advanced suffix. Each application has unique requirements. For example:
Motors and generators need magnets with high coercivity and temperature resistance.
Consumer electronics often use mid-grade magnets for a balance between strength and cost.
Medical devices may require special coatings or lower grades to ensure safety.
Tip: Always match the magnet grade and suffix to the actual working environment and performance needs. Over-specifying can waste resources, while under-specifying can lead to failure.
Engineers and designers should review the application’s temperature range, required pull force, and safety needs before making a final choice. This approach ensures the magnet will perform reliably and efficiently.
Selecting the right magnet grade ensures reliable performance and cost efficiency. Engineers should match magnet strength and temperature resistance to each application. The tables in this guide help users compare grades and suffixes quickly. Organizations that use outcome-based frameworks, like the Magnet Model, see measurable improvements in quality and value.
SOE Domain | Impact and Value |
|---|---|
Transformational Leadership | Improved outcomes, cost savings |
Advocacy and Influence | Better resource use, higher retention |
Professional Development | Cost effectiveness, enhanced engagement |
Using clear benchmarks and measurable results supports better magnet selection and long-term success.
FAQ
What does the grade number on a neodymium magnet mean?
The grade number shows the magnet’s maximum energy product, measured in Mega-Gauss-Oersteds (MGOe). Higher numbers indicate stronger magnets. For example, N52 is stronger than N35.
Why do some magnet grades have suffix letters like "SH" or "EH"?
Suffix letters indicate the magnet’s temperature resistance. “SH” stands for Super High, and “EH” means Extra High. These suffixes help users select magnets for high-temperature environments.
Can a higher grade magnet always replace a lower grade one?
Not always. Higher grade magnets provide more strength but may cost more or have lower temperature tolerance. Engineers must match the magnet’s grade to the application’s needs.
How do I choose the right neodymium magnet grade for my project?
Consider the required magnetic strength, operating temperature, and environment. Use tables to compare grades and suffixes. Select a grade that meets or exceeds your project’s demands.
Are neodymium magnets safe to use at home?
Neodymium magnets are safe when handled properly. Strong magnets can pinch skin or damage electronics. Keep them away from children and sensitive devices.
Do neodymium magnets lose strength over time?
Neodymium magnets retain their strength for many years if used within their rated temperature and environment. Exposure to high heat or physical damage can cause permanent loss.
What is the difference between N35 and N52 magnets?
N52 magnets are stronger than N35 magnets of the same size. The difference comes from their maximum energy product. N52 suits high-performance tasks, while N35 fits general use.
Can neodymium magnets work in extreme cold?
Yes. Neodymium magnets perform well at low temperatures, even below -100°C. Their strength may increase in cold environments, making them reliable for many applications.
