Samarium iron nitrogen magnets (SmFeN)
The magnet solution
for more resilient supply chains
SmFeN magnets: a neodymium alternative that eases supply chain pressure
With our application-specific developed SmFeN magnets we offer a high-performance alternative to neodymium magnets. The magnetic alloy of samarium, iron and nitrogen is referred to as samarium iron nitride, or SmFeN.
SmFeN is particularly suitable for applications that need to combine high magnetic performance, thermal stability and a more resilient raw material supply. Plastic-bonded SmFeN magnets combine high magnetic performance with good oxidation resistance and a low temperature coefficient – without neodymium and without heavy rare earths.
SmFeN therefore positions between high-performance neodymium magnets and robust ferrite magnets. Max Baermann supports you with the material-appropriate design, development and series production of an application-specific SmFeN solution.
Cost-efficient alternative to other rare earth magnets
High-performance option for demanding operating conditions
Technical properties of magnets made from samarium iron nitride (SmFeN)
SmFeN magnets combine high magnetic performance with a robust property profile for industrial applications. The material is based on samarium, iron and nitrogen and contains neither neodymium nor heavy rare earths. This makes it particularly interesting where technical performance and supply chain resilience have to be combined.
Plastic-bonded SmFeN magnets achieve high energy densities and remanence values of up to 0.85 tesla, generating a strong, permanent magnetic field. They are also characterized by high resistance to demagnetization and good thermal stability.
Because SmFeN is inherently resistant to oxidation, the material can also offer advantages over more corrosion- susceptible magnet solutions in many applications. For plastic-bonded versions, the maximum operating temperature depends on the polymer binder selected and can reach up to +150 °C.
| Property | Plastic-bonded SmFeN magnets |
|---|---|
| Field strength | up to 0.85 tesla |
| Maximum operating temperature | up to +150 °C (depending on the plastic binder) |
| Stability | High resistance to demagnetization, with jHc values of up to 1,400 kA/m; low temperature dependence due to the low temperature coefficient of -0.06 %/K, compared with -0.2 %/K for strontium ferrite and -0.11 %/K for neodymium-iron-boron. |
Technical properties of magnets made from samarium iron nitride (SmFeN)
SmFeN magnets combine high magnetic performance with a robust property profile for industrial applications. The material is based on samarium, iron and nitrogen and contains neither neodymium nor heavy rare earths. This makes it particularly interesting where technical performance and supply chain resilience have to be combined.
Plastic-bonded SmFeN magnets achieve high energy densities and remanence values of up to 0.85 tesla, generating a strong, permanent magnetic field. They are also characterized by high resistance to demagnetization and good thermal stability.
Because SmFeN is inherently resistant to oxidation, the material can also offer advantages over more corrosion- susceptible magnet solutions in many applications. For plastic-bonded versions, the maximum operating temperature depends on the polymer binder selected and can reach up to +150 °C.
| Plastic-bonded SmFeN magnets | |
|---|---|
| Field strength | up to 0.85 tesla |
| Maximum operating temperature | up to +150 °C (depending on the plastic binder) |
| Stability | High resistance to demagnetization, with jHc values of up to 1,400 kA/m; low temperature dependence due to the low temperature coefficient of -0.06 %/K, compared with -0.2 %/K for strontium ferrite and -0.11 %/K for neodymium-iron-boron. |
Variants and fields of application
We can produce SmFeN magnets as plastic-bonded magnetic components for sensors, rotors and other technical assemblies across a wide range of industries. Discover typical applications for our custom samarium iron nitride magnets:
Plastic-bonded magnets made from SmFeN
Unlike conventional sintered NdFeB magnets, SmFeN magnets are industrially produced primarily as injection-molded, plastic-bonded magnets. The reason: conventional sintering processes would thermally destroy the Sm-Fe-N magnetic phase and thus irreversibly impair the magnetic properties.
The manufacturing advantage lies in the combination of high magnetic performance and versatility together with extensive geometric design freedom. Thanks to this production process, application-specific magnet requirements can be met easily, even for complex geometries. This often means that complicated assembly processes are simplified, additional components are eliminated or parts can be designed more compactly. B2B customers therefore gain powerful magnet alternatives that also bring design advantages and enable simplified series production. Max Baermann combines many years of experience with strong expertise in developing and manufacturing plastic-bonded SmFeN magnets.
Note: the appropriate binder materials are selected on an application-specific basis.
Use as a magnetic component in rotors
Max Baermann develops SmFeN magnets as application-specific rotor components for industrial drives and motors, mechanical engineering and the automotive industry. In rotor applications in particular, SmFeN offers a strong property profile: high magnetic performance, high coercivity and comparatively stable field strength across a wide temperature range.
The plastic-bonded design can also reduce eddy current losses compared with electrically conductive, solid magnet solutions. Together with a magnetization pattern designed to suit the application, the electrically insulating polymer matrix can help reduce eddy current losses and additional heating in rotor applications.
Combined with good oxidation resistance and high resistance to demagnetization, SmFeN is therefore particularly suitable for thermally and electromagnetically demanding rotor applications. This allows rotors to be designed to save space and to combine several functions directly in a single component.
Use as a magnetic component in sensors
Max Baermann also develops SmFeN magnets as sensor components for angle, position and speed detection. The magnet solution is designed down to the last detail to suit the measuring principle and the sensor’s installation situation. This results in magnetic components that are as robust and economically efficient as possible in the specific application while always functioning precisely. Our standard: low angular errors, perfect magnetic field curves and homogeneous magnetic fields.
Due to the low temperature coefficient of SmFeN, the magnetic field is stable across a wide temperature range. This can reduce temperature-related deviations in the sensor signal – an essential prerequisite for highly precise, reproducible and reliable measurement results. Together with users and manufacturers of magnetic sensors, we design our magnets for optimum performance, so that modern sensor systems which are robust to stray fields can be realized with our support.
The result is robust and economically feasible magnetic components that also function precisely under changing operating conditions. Our standard: low angular errors, reproducible magnetic field curves and homogeneous magnetic fields designed to suit the application.
More permanent magnets in our portfolio
Let us advise you on the perfect material for your magnet solution
Are you looking for SmFeN magnets for a specific technical application, or would you like to explore whether neodymium magnets in your product can be replaced? Max Baermann supports you with material selection, magnetic design, development, prototyping and series production.