Neodymium Disc Magnet – 20mm x 10mm | N45H | High Temperature

Description

The Neodymium Disc Magnet – 20mm x 10mm | N45H | High Temperature is a powerful rare earth permanent magnet manufactured from N45H grade Neodymium Iron Boron (NdFeB). Measuring 20mm in diameter x 10mm thick, this high-performance round magnet combines strong magnetic energy density with an elevated-temperature material grade designed to provide improved resistance to irreversible demagnetisation under higher operating temperatures.

The N45H magnetic grade is particularly useful in engineering, industrial and technical applications where conventional neodymium magnets may not provide sufficient temperature resistance. The H classification identifies a high-coercivity neodymium material designed for improved magnetic stability under elevated-temperature conditions.

With its substantial 10mm thickness and 20mm diameter, this magnet provides a compact cylindrical disc profile suitable for magnetic holding, positioning, alignment, sensors, machinery, fixtures and custom magnetic assemblies.

Potential applications include industrial equipment, engineering, manufacturing, automotive components, electronic assemblies, magnetic switching systems, instrumentation, product development and OEM manufacturing.

Also known as a 20mm high-temperature neodymium disc magnet, N45H rare earth magnet, heat-resistant NdFeB magnet, high-coercivity neodymium disc or 20mm x 10mm round magnet, this permanent magnet provides continuous magnetic operation without electricity, batteries or charging.

Key Features

• Diameter: 20mm

• Thickness: 10mm

• Dimensions: 20mm diameter x 10mm thick

• Shape: Disc / Round

• Material: Neodymium Iron Boron (NdFeB)

• Magnetic grade: N45H

• Temperature classification: High Temperature

• Magnet type: Rare Earth Permanent Magnet

• High-coercivity H grade

• Enhanced resistance to irreversible demagnetisation at elevated temperatures

• Compact cylindrical disc design

• 2:1 diameter-to-thickness ratio

• High magnetic performance relative to size

• Suitable for engineering and manufacturing

• Useful for industrial equipment and machinery

• Suitable for sensors and instrumentation

• Ideal for custom magnetic assemblies

• Permanent magnetic operation

• No electricity or batteries required

Common Applications

• High-temperature magnetic assemblies

• Industrial machinery

• Engineering equipment

• Manufacturing

• Automotive components

• Electronic assemblies

• Magnetic holding

• Positioning and alignment

• Fixtures and jigs

• Magnetic closures

• Equipment housings

• Sensors

• Hall-effect sensing systems

• Reed switches

• Position detection

• Proximity sensing

• Magnetic switching

• Instrumentation

• Research and development

• Laboratory equipment

• Prototypes

• OEM manufacturing

• Custom magnetic systems

Suitability depends on the required magnetic performance, operating temperature, magnetisation direction and complete assembly design.

N45H High-Temperature Neodymium Grade

One of the defining features of this magnet is its N45H magnetic material grade.

N45H belongs to the family of elevated-temperature neodymium magnets designed for applications requiring improved resistance to irreversible magnetic losses.

The grade designation contains two important elements:

N45: Identifies the magnetic energy grade of the NdFeB material.

H: Indicates a high-coercivity neodymium grade with enhanced resistance to demagnetisation at elevated temperatures.

This combination makes N45H useful for applications where designers need both high magnetic energy density and improved temperature stability.

Why Is High Coercivity Important?

Coercivity describes a magnetic material's resistance to demagnetisation.

Higher intrinsic coercivity can help a magnet resist irreversible magnetic losses caused by:

• Elevated temperatures

• Opposing magnetic fields

• Demanding magnetic circuits

• Unfavourable operating conditions

This makes N45H a useful choice for engineering applications where magnetic stability is an important consideration.

High-Temperature Magnetic Performance

Neodymium magnets generally experience a reduction in magnetic output as temperature increases.

Some of this reduction is reversible, meaning the magnetic performance can recover as the magnet cools.

However, excessive temperatures or adverse magnetic conditions can cause irreversible demagnetisation.

N45H is designed to provide improved resistance to this irreversible magnetic loss compared with corresponding standard-temperature neodymium grades.

The actual temperature capability of a finished magnet depends on:

• Magnetic material grade

• Magnet dimensions

• Magnetisation direction

• Magnetic circuit

• External magnetic fields

• Operating load line

• Duration of temperature exposure

• Surrounding components

Important: A specific maximum operating temperature for this finished magnet has not been supplied and should be confirmed before use in temperature-critical applications.

20mm x 10mm Disc Magnet Design

This magnet measures 20mm in diameter x 10mm thick, giving it a substantial cylindrical disc profile.

Its diameter is twice its thickness, creating a 2:1 diameter-to-thickness ratio.

This geometry can be useful where:

• A round magnetic component is preferred

• A broad circular face is required

• The magnet needs to fit inside a cylindrical recess

• Installation space is limited

• A compact magnetic holding component is needed

• The magnet will be integrated into machinery or equipment

The stated dimensions describe the physical geometry of the magnet and do not indicate its pull force or holding capacity.

Engineering and Industrial Applications

N45H neodymium disc magnets can be incorporated into engineered products where magnetic performance and elevated-temperature resistance are important.

Potential applications include:

• Industrial machinery

• Manufacturing equipment

• Magnetic positioning systems

• Fixtures and jigs

• Mechanical assemblies

• Equipment housings

• Automated systems

• Custom magnetic devices

• Prototype mechanisms

For applications involving heat, vibration or dynamic loading, the complete assembly should be tested under realistic operating conditions.

Magnetic Holding and Retention

The circular profile of this magnet may be suitable for magnetic holding and retention applications.

Potential uses include:

• Removable components

• Magnetic closures

• Access panels

• Equipment covers

• Positioning fixtures

• Product assemblies

Holding performance depends on the magnetisation direction, contact area, target material, air gaps and load direction.

Magnetic retention should not replace engineered mechanical restraint where failure could create a safety hazard.

Sensors and Magnetic Switching

Neodymium disc magnets can be used as magnetic field sources in suitable sensing systems.

Potential applications include:

• Hall-effect sensors

• Reed switches

• Position sensors

• Proximity detection

• Magnetic switching

• Movement detection

• Instrumentation

Sensor performance depends on:

• Magnetisation direction

• Pole orientation

• Magnet-to-sensor distance

• Sensor sensitivity

• Magnetic field strength

• Operating temperature

• Surrounding ferromagnetic materials

The magnetisation direction of this product has not been supplied and should be confirmed where field orientation is important.

Magnetisation Direction

Disc magnets can be manufactured with different magnetic orientations.

A 20mm diameter x 10mm thick disc magnet could potentially be:

• Axially magnetised through its 10mm thickness

• Diametrically magnetised across its 20mm diameter

• Manufactured with another specialised magnetisation configuration

The actual magnetisation direction and pole configuration have not been supplied and should not be assumed from the disc shape.

Confirm the magnetic orientation before incorporating the magnet into a design requiring a specific field direction.

Magnetic Performance

The practical magnetic performance of this N45H disc magnet depends on:

• Magnetic material properties

• Magnet dimensions

• Magnetisation direction

• Pole configuration

• Magnetic circuit design

• Target material

• Target steel thickness

• Contact area

• Surface condition

• Air gaps

• Operating temperature

• Load direction

No specific pull force or surface Gauss rating has been supplied.

These values should not be inferred from the N45H designation alone.

Direct Pull vs Shear Force

Magnetic holding performance varies according to load direction.

Direct pull occurs when the magnet is separated perpendicular to the attracting surface.

Shear loading occurs when the magnet is encouraged to slide parallel to the target surface.

Shear performance may be influenced by:

• Surface friction

• Surface coatings

• Air gaps

• Vibration

• Installation orientation

• Mechanical leverage

Where the magnet is used for holding or retention, performance should be tested under the actual operating conditions.

Air Gaps Reduce Magnetic Attraction

Magnetic attraction decreases as the distance between the magnet and target increases.

Potential sources of air gaps include:

• Adhesive

• Paint

• Powder coating

• Plastic housings

• Protective films

• Mechanical clearance

• Surface irregularities

For applications requiring maximum magnetic interaction, unnecessary separation should be minimised.

Bonding and Installation

Adhesive bonding may be suitable for incorporating this magnet into a product or assembly.

Before installation:

1. Confirm magnetisation direction and polarity.

2. Check the intended magnetic arrangement.

3. Clean the bonding surfaces.

4. Remove dust, oil and grease.

5. Select an adhesive compatible with the magnet's actual coating.

6. Confirm the adhesive is suitable for the intended operating temperature.

7. Provide appropriate dimensional clearance.

8. Avoid force-fitting or excessive clamping pressure.

9. Allow the adhesive to cure according to the manufacturer's instructions.

The exact coating or plating of this magnet has not been supplied, so adhesive compatibility should be confirmed before permanent installation.

For elevated-temperature applications, the adhesive, housing and surrounding components must also be suitable for the intended temperature range.

Avoid Force-Fitting

Neodymium Iron Boron is a hard but brittle magnetic material.

Do not force the magnet into an undersized hole, recess or housing.

Excessive mechanical pressure can cause:

• Chipping

• Cracking

• Fracturing

• Damage to the protective coating

Provide appropriate dimensional clearance and use a suitable retention method.

Do Not Machine Neodymium Magnets

Finished neodymium magnets should not normally be mechanically modified.

Avoid:

• Drilling

• Cutting

• Grinding

• Filing

• Crushing

• Machining

These processes can damage the brittle NdFeB material and its protective surface.

If a different size or shape is required, use a magnet manufactured to the required dimensions.

Compatible Magnetic Materials

Neodymium magnets attract suitable ferromagnetic materials, including:

• Iron

• Mild steel

• Magnetic steel

• Compatible ferromagnetic components

They do not effectively attract inherently non-magnetic materials such as:

• Aluminium

• Copper

• Brass

• Plastic

• Timber

• Glass

Many stainless steel grades may also be weakly magnetic or non-magnetic.

Test the intended target material where magnetic compatibility is important.

N45H vs Standard N45 Neodymium Magnets

Both N45 and N45H are high-performance Neodymium Iron Boron grades.

The key difference is their resistance to demagnetisation under elevated-temperature conditions.

N45H is designed to provide improved resistance to irreversible demagnetisation compared with standard N45 material.

N45H may be preferred where:

• Elevated temperatures are expected

• Magnetic stability is important

• The assembly may experience demagnetising fields

• Long-term magnetic performance is a design consideration

• A high-coercivity rare earth material is required

Standard N45 may be suitable for applications operating within its verified temperature and magnetic requirements.

N45H Neodymium vs Ferrite Magnets

Neodymium magnets generally provide higher magnetic energy density than conventional ferrite magnets.

N45H neodymium may be preferred for:

• Compact magnetic assemblies

• High magnetic performance relative to size

• Elevated-temperature NdFeB applications

• Engineering components

• Sensors and instrumentation

• Custom magnetic systems

Ferrite magnets may be preferred for:

• More economical applications

• Larger magnetic components

• Applications benefiting from natural corrosion resistance

• Certain elevated-temperature applications where lower magnetic energy density is acceptable

The appropriate magnetic material depends on magnetic performance, temperature requirements, environmental conditions and design constraints.

Permanent Magnetic Operation

This N45H disc magnet is a permanent magnet.

It requires:

• No electricity

• No batteries

• No charging

• No external power supply

Its magnetic field remains continuously active during normal use.

Technical Specifications

Compliance & Safety

Neodymium magnets can attract rapidly and forcefully to other magnets and ferromagnetic objects.

Brittle Material: Neodymium Iron Boron is hard but brittle. Magnets can chip, crack or fracture if dropped, struck or allowed to collide.

Pinch Hazards: Keep fingers and skin clear when allowing magnets to approach steel surfaces or other magnets.

Do Not Machine: Avoid drilling, cutting, grinding or modifying the magnet.

Medical Devices: Keep magnets at an appropriate distance from pacemakers, implanted medical devices and magnetically sensitive equipment.

Children: Keep magnets securely away from babies and children. Swallowed magnets can cause severe internal injuries and require urgent medical attention.

High-Temperature Use: Confirm the maximum operating temperature of the finished magnet and ensure that adhesives, housings and surrounding components are suitable for the intended environment.

Lifting Applications: This magnet is not certified lifting equipment and must not be used for overhead or safety-critical lifting.

Frequently Asked Questions

What size is this magnet?

The magnet measures 20mm in diameter x 10mm thick.

What does N45H mean?

N45H is a high-coercivity neodymium magnetic material grade designed for improved resistance to irreversible demagnetisation at elevated temperatures.

Is N45H a high-temperature magnet?

Yes. N45H is classified as an elevated-temperature neodymium grade. However, the specific maximum operating temperature of the finished magnet should be confirmed before use.

Is N45H stronger than standard N45?

Both grades belong to the N45 magnetic energy classification. N45H is designed to provide improved resistance to irreversible demagnetisation under elevated-temperature conditions rather than necessarily providing greater room-temperature pull force.

Is this magnet axially magnetised?

The magnetisation direction has not been supplied and should be confirmed before use in applications requiring a specific pole orientation.

Can this magnet be used in industrial machinery?

It may be suitable for industrial machinery where its magnetic properties, dimensions and verified temperature capability meet the application requirements.

Can I glue this magnet into a housing?

Yes, provided the adhesive is compatible with the magnet's actual coating and suitable for the intended temperature and mechanical conditions.

Can this magnet be drilled or cut?

No. Neodymium is brittle and should not be drilled, cut, ground or machined.

Does N45H mean 45kg pull force?

No. N45H identifies the magnetic material grade and elevated-temperature classification. It does not indicate pull force or lifting capacity.

Related Products

Customers considering this product may also be interested in:

• High-Temperature Neodymium Magnets

• Neodymium Disc Magnets

• Neodymium Cylinder Magnets

• Neodymium Block Magnets

• N45 Neodymium Magnets

• Samarium Cobalt Magnets

• Custom-Made Magnets

Please Note

The Neodymium Disc Magnet – 20mm x 10mm | N45H | High Temperature measures 20mm in diameter x 10mm thick and is manufactured from N45H grade Neodymium Iron Boron.

The N45H designation identifies a high-coercivity, elevated-temperature neodymium grade designed to provide enhanced resistance to irreversible demagnetisation.

A specific maximum operating temperature for the finished magnet has not been supplied and should not be assumed from the grade designation alone.

No specific pull force, Gauss rating, coating or plating, magnetisation direction, pole configuration or dimensional tolerance has been supplied.

Actual magnetic performance depends on the magnetic material, magnetisation configuration, magnetic circuit, operating temperature, target material, target steel thickness, contact area, air gaps and installation geometry.

Neodymium is a hard and brittle magnetic material. Avoid impact, force-fitting, drilling, cutting, grinding or machining.

This magnet is not certified lifting equipment and should not be used for overhead or safety-critical lifting.