Magnet Materials Grades - Shanghai Young Magnet Co.,Ltd

Magnet Materials & Grades

Choosing the right permanent magnet is not simply a matter of selecting the strongest material. Magnetic performance, operating temperature, corrosion resistance, available space, cost, magnetization requirements, and application conditions all affect the final material selection.

We manufacture and supply a range of permanent magnet materials, including NdFeB, Ferrite, SmCo, and AlNiCo, with different magnetic grades and customized specifications for industrial and OEM applications.

Quick Material Selection Guide

Material	Key Advantage	Typical Selection Reason	Typical Applications
NdFeB	Very high magnetic performance	High magnetic force in compact designs	Motors, sensors, actuators, generators, electronics
Ferrite	Cost-effective and corrosion resistant	Large-volume and cost-sensitive applications	Motors, speakers, pumps, appliances
SmCo	High temperature and corrosion resistance	High-performance applications in demanding environments	Aerospace, sensors, motors, instrumentation
AlNiCo	Excellent temperature stability	High-temperature and stable-field applications	Sensors, meters, motors, industrial equipment

Permanent Magnet Materials We Supply

1. NdFeB Magnets
NdFeB (Neodymium-Iron-Boron) is the highest-performance permanent magnet material among the four material families covered on this page in terms of maximum magnetic energy density. NdFeB magnets are widely selected when high magnetic force, compact size, and high energy density are important design requirements.
Available grades can be selected according to required magnetic performance and operating temperature. Standard and high-temperature grades include N-series, M, H, SH, UH, and EH grades, depending on the required specification.

Key Characteristics:

Very high maximum energy product
High remanence
High magnetic force in compact dimensions
Wide range of magnetic grades
High-temperature grades available
Multiple surface coating options
Suitable for precision industrial applications
Available in customized shapes and dimensions

Typical Applications:

Electric motors and servo motors
Brushless direct current motors
Generators and wind power equipment
Automotive components and sensors
Actuators and magnetic couplings
Electronic equipment and industrial automation

2. NdFeB Magnet Grades
NdFeB grades are generally identified by their magnetic performance and temperature capability. A typical NdFeB grade consists of a base grade such as N35, N38, N40, N42, N45, N48, N50, N52 or higher-performance grades, followed by temperature-related suffixes such as M, H, SH, UH, EH, depending on the specification.

Designation Examples:
N42: N represents the standard temperature grade family, while 42 indicates the approximate maximum energy product level in MGOe.
N42SH: N42 represents the base magnetic performance, and SH denotes the higher-temperature grade family.

Common NdFeB Grade Families:

N Series: Standard-temperature applications
M Series: Improved temperature capability
H Series: Higher operating temperature
SH Series: Higher temperature resistance
UH Series: Very high temperature applications
EH Series: Extremely demanding high-temperature applications

3. Ferrite Magnets
Ferrite magnets, also known as ceramic magnets, are widely used permanent magnetic materials based primarily on iron oxide combined with strontium or barium compounds. Compared with rare-earth magnets, ferrite offers a lower material cost, excellent corrosion resistance, good resistance to demagnetization, and stable performance for many industrial applications.
Ferrite is particularly suitable where cost efficiency, corrosion resistance, volume production, and stable magnetic performance are more important than achieving the highest possible magnetic strength.

Key Characteristics:

Cost-effective material structure
Excellent corrosion resistance
Good resistance to demagnetization
Stable magnetic performance
Good electrical resistivity
Suitable for high-volume production
Available in isotropic and anisotropic grades

Typical Applications:

Alternating current and direct current motors
Loudspeakers and acoustic devices
Water pumps and cooling fans
Sensors and automotive components
Household appliances
Magnetic separators and industrial assemblies

4. Ferrite Magnet Grades
Ferrite grades are commonly selected according to their remanence, coercive force, intrinsic coercivity, and maximum energy product. Depending on the manufacturing system and applicable standard, ferrite grades may be identified by designations such as Y30, Y32, Y35, Y30BH, and related material grades, including specific series such as YC29, YC29H, YC30, YC30B, YC31, YC32, YC33, and YC34.

Important Ferrite Parameters:

Remanence (Br): Magnetic flux density remaining after magnetization.
Coercive Force (Hcb): Resistance to demagnetization under an external magnetic field.
Intrinsic Coercivity (Hcj): Resistance to irreversible demagnetization.
Maximum Energy Product ((BH)max): Maximum magnetic energy density.
Density: Material density.

5. SmCo Magnets
Samarium Cobalt (SmCo) is a rare-earth permanent magnet material known for its high magnetic performance, excellent temperature stability, and strong resistance to corrosion. SmCo is often considered when an application requires reliable magnetic performance under elevated temperatures or demanding environmental conditions.
Compared with NdFeB, SmCo generally offers better high-temperature stability and corrosion resistance, although material cost is typically higher.

Key Characteristics:

High magnetic performance
Excellent temperature stability
High Curie temperature
Excellent corrosion resistance
Good resistance to demagnetization
Suitable for demanding industrial environments

Typical Applications:

Aerospace equipment
High-temperature motors
Sensors and optical encoders
Industrial pumps and instrumentation
Magnetic couplings and automation equipment

6. AlNiCo Magnets
AlNiCo (Aluminum-Nickel-Cobalt) is a permanent magnet alloy known for its excellent thermal stability, high Curie temperature, and reliable magnetic performance at elevated temperatures. AlNiCo magnets are available in both cast and sintered forms and can be produced in various shapes, including bars, rods, rings, blocks, arcs, and customized configurations.

Key Characteristics:

Excellent temperature stability
High Curie temperature
Good corrosion resistance
Stable magnetic output at elevated temperatures
Cast and sintered manufacturing options
Suitable for complex magnetic structures

Typical Applications:

Industrial sensors and measuring instruments
High-temperature equipment
Specialized motors and generators
Automation and detection systems
Magnetic instruments and positioning systems

Permanent Magnet Material Comparison

Property	NdFeB	Ferrite	SmCo	AlNiCo
Magnetic Strength	Very High	Low to Medium	High	Medium
Energy Density	Very High	Low	High	Medium
Temperature Stability	Medium to High	Good	Excellent	Excellent
Corrosion Resistance	Requires consideration	Excellent	Excellent	Good
Cost	Higher	Low	High	Medium to High
Compact Design	Excellent	Limited	Good	Moderate
High-Temperature Use	Grade dependent	Good	Excellent	Excellent
Typical Position	High-performance	Cost-effective	High-temperature	Thermal stability

How to Choose the Right Magnet Grade

The highest grade is not always the best choice. A suitable magnet grade should be selected according to actual application requirements.

Required Magnetic Performance: Determine the required remanence (Br), coercive force (Hcb), intrinsic coercivity (Hcj), maximum energy product ((BH)max), and magnetic flux density at the working point.

Operating Temperature: Determine the normal operating temperature, maximum operating temperature, temperature cycling conditions, and possible overheating conditions. Higher-temperature grades may be required when exposed to elevated temperatures.

Available Installation Space: If the magnet must fit into a compact structure, a higher-energy-density material such as NdFeB may reduce the required magnet volume.

Corrosion Environment: Consider humidity, water exposure, salt spray, chemicals, and outdoor exposure. Material selection and surface treatment should be evaluated together.

Cost Target: For high-volume, cost-sensitive applications, ferrite may provide a better overall solution. For compact, high-performance applications, NdFeB offers better design efficiency. For high-temperature environments, SmCo or AlNiCo provides superior long-term stability.

Key Magnetic Properties Explained

Remanence (Br): Indicates the magnetic flux density remaining in the magnet after the magnetizing field is removed. A higher Br generally indicates stronger magnetic output under comparable conditions.

Coercive Force (Hcb): Indicates the magnet's resistance to demagnetization when exposed to an external magnetic field.

Intrinsic Coercivity (Hcj): Represents the magnet's resistance to irreversible demagnetization and is particularly important for applications involving elevated temperatures or strong opposing magnetic fields.

Maximum Energy Product ((BH)max): Represents the maximum magnetic energy density of the magnet material and serves as an important parameter when comparing permanent magnet materials and evaluating compact designs.

Curie Temperature (Tc): The temperature at which a magnetic material loses its long-range ferromagnetic or ferrimagnetic ordering. This should not be confused with the maximum recommended operating temperature.

Material Selection by Application

Application Requirement	Recommended Material Direction
Maximum magnetic force in limited space	NdFeB
Cost-sensitive high-volume production	Ferrite
High-temperature permanent magnet	SmCo / AlNiCo
Strong corrosion resistance	Ferrite / SmCo
Compact motor design	NdFeB
Loudspeakers	Ferrite / NdFeB
High-temperature sensors	SmCo / AlNiCo
Industrial instrumentation	AlNiCo / SmCo
Automotive motors	NdFeB / Ferrite

Standard and Custom Grades

Not every application can be solved with a standard grade. For OEM and industrial projects, magnet selection often requires optimization of magnetic properties, operating temperatures, dimensions, magnetization directions, surface treatments, mechanical tolerances, magnetic circuits, cost targets, and production volumes.

We evaluate application requirements and recommend suitable materials and grades based on customer technical specifications, drawings, samples, or application conditions.

Material Selection Is Not Based on Grade Alone

A magnet grade alone does not determine whether a magnet will work correctly in a final product. Actual magnetic performance is affected by:

Magnet dimensions and shape
Magnetization direction and pole configuration
Magnetic circuit design, air gap, and working point
Operating temperature and thermal cycling

Adjacent magnetic materials and demagnetizing field
Surface treatment and assembly method
Overall application environment

For this reason, material selection should be evaluated together with complete magnetic and mechanical requirements.

What Information Should You Send Us?

To recommend the right magnet material and grade, please provide as much of the following information as available:

Product Requirements

Magnet material (if specified), magnet grade (if known), dimensions (length x width x thickness), shape, magnetization direction, number of poles, and required magnetic performance.

Application Conditions

Application or equipment type, normal operating temperature, maximum operating temperature, indoor or outdoor use, humidity or water exposure, chemical environment, and expected service life.

Production Requirements

Annual quantity, order quantity, prototype or mass production requirements, tolerances, surface treatment, packaging requirements, and target delivery schedule.

Drawings & Samples

2D drawings, 3D computer-aided design files, existing magnet samples, magnetic test reports, material specifications, and performance requirements.

Our engineers can review your requirements and recommend the appropriate magnet material, grade, dimensions, and manufacturing solution.

Technical Data and Quality Verification

Material selection should be supported by measurable technical data. Depending on the material and specification, technical documentation may include material grades, magnetic properties (Br, Hcb, Hcj, (BH)max), density, maximum operating temperature, dimensional tolerances, surface treatment, magnetization direction, inspection records, material certificates, and test reports.
For project-specific requirements, technical documentation can be discussed and confirmed before production.

Frequently Asked Questions

Q: Which permanent magnet material is the strongest?

A: NdFeB generally provides the highest magnetic energy density among the four main permanent magnet material families. However, the strongest material is not necessarily the best choice for every application.

Q: How do I choose between NdFeB and Ferrite?

A: Choose NdFeB when high magnetic performance and compact size are important. Ferrite is often preferred for cost-sensitive, high-volume applications where extremely high magnetic strength is not required.

Q: What does N52 mean?

A: N52 is an NdFeB grade designation associated with a high maximum energy product level. Grade selection should still consider temperature, coercivity, dimensions, and application conditions.

Q: What do SH, UH, and EH mean in NdFeB grades?

A: SH, UH, and EH are commonly used suffixes to identify higher-temperature NdFeB grade families. The appropriate grade depends on actual operating temperatures and demagnetization conditions.

Q: Are ferrite magnets corrosion resistant?

A: Yes. Ferrite magnets generally have excellent corrosion resistance because of their ceramic material structure and are commonly used in humid or outdoor environments.

Q: When should I choose SmCo instead of NdFeB?

A: SmCo should be considered when the application requires high magnetic performance combined with elevated-temperature stability and excellent corrosion resistance.

Q: When is AlNiCo a better choice?

A: AlNiCo is particularly suitable for applications requiring excellent thermal stability and stable magnetic performance at elevated temperatures.

Q: Can you recommend a magnet grade if we don't know which one to use?

A: Yes. If you provide the magnet dimensions, application, operating temperature, magnetic requirements, working environment, and quantity, our technical team can recommend a suitable material and grade.