Neodymium Disc Magnet – 23.6mm x 20mm | N42

The Neodymium Disc Magnet – 23.6mm x 20mm | N42 is a powerful rare earth permanent magnet measuring 23.6mm in diameter x 20mm thick. Manufactured from N42 grade Neodymium Iron Boron (NdFeB), this substantial round magnet provides strong magnetic performance relative to its compact dimensions and is suitable for industrial, engineering, manufacturing, holding, positioning, sensing, product assembly, research and custom OEM applications.

With a 23.6mm diameter and substantial 20mm thickness, this magnet has a deep cylindrical disc profile rather than the thin proportions commonly associated with smaller disc magnets. Its compact footprint and significant magnetic material volume make it useful for appropriately designed magnetic assemblies where strong permanent magnetic performance is required.

Also known as an N42 neodymium disc magnet, rare earth disc magnet, NdFeB round magnet, 23.6mm neodymium magnet or rare earth round magnet, this permanent magnetic component operates continuously without electricity, batteries or charging.

Key Features

• Diameter: 23.6mm
• Thickness / height: 20mm
• Dimensions: 23.6mm diameter x 20mm thick
• Shape: Disc / round
• Material: Neodymium Iron Boron (NdFeB)
• Magnetic grade: N42
• Magnet type: Rare earth permanent magnet
• Substantial 20mm thick profile
• Strong magnetic performance relative to size
• Suitable for industrial and engineering applications
• Useful for magnetic holding and attraction
• Suitable for positioning and alignment systems
• Useful for sensors and instrumentation
• Suitable for fixtures and jigs
• Useful for product and mechanical assemblies
• Suitable for research and prototype development
• Suitable for custom OEM magnetic assemblies
• Permanent magnetic operation
• No electricity, batteries or charging required

Common Applications

• Engineering
• Manufacturing
• Industrial equipment
• Magnetic holding systems
• Product assemblies
• Mechanical components
• Positioning systems
• Alignment applications
• Fixtures and jigs
• Sensors and instrumentation
• Position detection
• Proximity sensing
• Magnetic switching
• Research and development
• Laboratory equipment
• Prototype devices
• Custom OEM magnetic assemblies

23.6mm Diameter x 20mm Thick Disc Magnet

This N42 neodymium magnet measures:

• 23.6mm diameter
• 20mm thickness

At 20mm thick, this product has a relatively deep profile for a disc magnet.

Its geometry can be useful for integration into:

• Circular recesses
• Equipment housings
• Mechanical assemblies
• Magnetic fixtures
• Product components
• Positioning systems
• Prototype equipment
• Custom magnetic assemblies

The stated dimensions describe the physical geometry of the magnet and do not represent its pull force, holding capacity or safe working load.

N42 Grade Neodymium Magnet

This disc magnet is manufactured from N42 grade Neodymium Iron Boron.

N42 is a high-performance neodymium grade commonly used where substantial permanent magnetic properties are required within compact dimensions.

N42 magnets can be useful where:

• Strong permanent magnetism is required
• Available installation space is limited
• A compact round magnet is preferred
• High magnetic energy density is desirable
• Higher magnetic performance than similarly sized ferrite magnets is required

The N42 designation identifies the magnetic material grade and does not indicate a 42kg pull force.

What Does N42 Mean?

The N42 grade describes the magnetic material used to manufacture the magnet.

The numerical designation relates to the maximum energy product of the Neodymium Iron Boron material and helps classify different neodymium grades.

When comparing magnets with identical dimensions, geometry and magnetisation configurations, different grades can provide different levels of magnetic performance.

N42 does not directly specify:

• Pull force
• Surface Gauss
• Holding capacity
• Safe working load
• Magnetisation direction
• Pole orientation

These characteristics depend on the finished magnet, magnetic circuit and application.

Neodymium Iron Boron Rare Earth Material

Neodymium Iron Boron is a high-performance rare earth permanent magnetic material widely used in engineering, manufacturing and modern product design.

NdFeB magnets provide high magnetic energy relative to their physical dimensions, making them useful for applications involving:

• Magnetic attraction
• Holding
• Positioning
• Alignment
• Sensing
• Switching
• Product integration
• Magnetic assemblies

Their high magnetic performance makes neodymium magnets particularly useful where installation space is restricted.

Magnetic Holding Applications

This N42 disc magnet can be incorporated into appropriately designed magnetic holding systems.

Potential applications include:

• Component retention
• Removable fixtures
• Magnetic positioning
• Equipment assemblies
• Product closures
• Display systems
• Workshop fixtures

Practical holding capacity depends on the complete magnetic circuit and should not be inferred from the N42 grade alone.

Positioning and Alignment

Round neodymium magnets can be incorporated into positioning and alignment systems.

Potential functions include:

• Component locating
• Repeatable positioning
• Magnetic alignment
• Assembly assistance
• Fixture positioning
• Prototype mechanisms

Where multiple magnets are used together, confirm their polarity and orientation before permanent installation.

Sensors and Instrumentation

N42 neodymium disc magnets may also be incorporated into magnetic sensing systems where their field configuration is suitable.

Potential applications include:

• Hall-effect sensors
• Reed switches
• Position sensors
• Proximity detection
• Magnetic switching
• Equipment monitoring
• Instrumentation

Sensor performance depends on:

• Magnetisation direction
• Pole orientation
• Magnet-to-sensor distance
• Sensor sensitivity
• Installation geometry
• Surrounding magnetic materials

The magnetisation configuration has not been supplied and should be confirmed where magnetic field direction is critical.

Magnetisation Direction

Disc magnets can be manufactured with different magnetisation configurations.

A 23.6mm diameter x 20mm thick disc magnet could potentially be:

• Axially magnetised through its 20mm thickness
• Diametrically magnetised across its 23.6mm diameter
• Manufactured with another specialised pole configuration

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

Confirm this specification where magnetic field orientation is important.

Magnetic Performance

Although this magnet is confirmed as N42 grade, practical magnetic performance depends on multiple factors.

These include:

• N42 material properties
• Magnetisation direction
• Pole configuration
• Magnetic circuit design
• Target steel composition
• Target steel thickness
• Available contact area
• Surface condition
• Air gaps
• Load direction
• Installation geometry

No specific pull force or magnetic flux density in Gauss has been supplied.

These values should not be estimated from the N42 designation or physical dimensions alone.

N42 Does Not Mean 42kg Pull Force

The N42 designation does not mean this magnet has a 42kg pull force.

N42 identifies the grade of the neodymium magnetic material.

Pull force is a separate performance measurement influenced by:

• Magnet dimensions
• Magnetisation direction
• Target material
• Target steel thickness
• Contact area
• Surface condition
• Air gaps
• Test configuration

A verified pull-force specification should be used where holding capacity is important.

Direct Pull vs Shear Force

Magnetic holding performance varies depending on the direction of the applied load.

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

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

Shear performance can be affected by:

• Surface friction
• Contact quality
• Surface coatings
• Installation orientation
• Air gaps
• Mechanical leverage
• Vibration

Test the completed assembly under realistic operating conditions where magnetic holding is important.

Air Gaps and Magnetic Attraction

Air gaps can significantly reduce the practical attraction of neodymium magnets.

Potential sources of separation include:

• Paint
• Powder coating
• Adhesive
• Plastic
• Protective films
• Product housings
• Dirt
• Rust
• Mechanical clearance

For maximum practical attraction, unnecessary separation between the magnet and magnetic target should generally be minimised.

Target Steel Thickness

Where this magnet is used against ferromagnetic steel, the properties of the target material influence magnetic performance.

Important factors include:

• Steel composition
• Steel thickness
• Target dimensions
• Available contact area
• Surface condition
• Magnetic saturation

Thin steel may not provide the same magnetic response as a suitably thick ferromagnetic target.

Testing against the actual target material is recommended for performance-critical applications.

Bonding a Neodymium Disc Magnet

This N42 disc magnet can be bonded into an appropriately designed housing or recess.

Before bonding:

• Confirm the required magnetic orientation
• Confirm polarity where multiple magnets are involved
• Clean both bonding surfaces
• Remove grease, dust and contamination
• Select an adhesive compatible with the magnet's actual surface finish
• Provide appropriate dimensional clearance
• Avoid force-fitting
• Allow the adhesive to cure according to its instructions

The specific coating or plating has not been supplied, so adhesive compatibility with the actual magnet surface should be confirmed.

Avoid Force-Fitting

Neodymium Iron Boron is hard but brittle.

Do not force this magnet into an undersized recess or housing.

Excessive mechanical pressure may cause:

• Chipping
• Cracking
• Splitting
• Fracturing
• Damage to the surface finish

Provide appropriate dimensional clearance and use a suitable bonding or mechanical retention method.

Do Not Machine Neodymium Magnets

Finished neodymium magnets should not be modified using conventional workshop methods.

Avoid:

• Drilling
• Cutting
• Grinding
• Crushing
• Machining

These processes can damage the brittle NdFeB magnetic material and any protective surface coating.

If another size or geometry is required, select a magnet manufactured to the appropriate dimensions.

Compatible Target Materials

Neodymium magnets attract suitable ferromagnetic materials, including:

• Mild steel
• Iron
• Magnetic steel
• Compatible ferromagnetic components

They will 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 and should be tested before relying on magnetic attraction.

N42 Neodymium vs Ferrite Disc Magnets

N42 neodymium and ferrite disc magnets provide different magnetic characteristics.

N42 neodymium disc magnets generally provide:

• Higher magnetic performance relative to size
• High magnetic energy density
• Strong performance from compact dimensions
• Advantages in space-restricted applications
• Suitability for engineered magnetic assemblies

Ferrite disc magnets generally provide:

• Lower cost
• Good natural corrosion resistance
• Good resistance to demagnetisation
• Suitability where larger magnet dimensions are acceptable

N42 neodymium is commonly selected where strong magnetic performance from a compact permanent magnet is required.

Permanent Magnetic Operation

This N42 neodymium disc 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

• Product Name: Neodymium Disc Magnet – 23.6mm x 20mm | N42
• Product Type: Neodymium Disc Magnet
• Alternative Names: N42 Neodymium Disc Magnet, Rare Earth Disc Magnet, NdFeB Round Magnet, Rare Earth Round Magnet, 23.6mm Neodymium Magnet
• Diameter: 23.6mm
• Thickness / Height: 20mm
• Dimensions: 23.6mm diameter x 20mm thick
• Shape: Disc / Round
• Magnetic Material: Neodymium Iron Boron (NdFeB)
• Magnetic Grade: N42
• Magnet Type: Rare Earth Permanent Magnet
• Magnetic Operation: Permanent
• Power Required: None
• Compatible Targets: Suitable ferromagnetic iron and steel
• Primary Functions: Magnetic attraction, holding, positioning, alignment, sensing, switching and product integration
• Typical Applications: Engineering, manufacturing, fixtures, sensors, machinery, product assemblies, research, prototypes and OEM magnetic assemblies

Safety and Handling

This is a substantial neodymium magnet and should be handled carefully around other magnets and ferromagnetic objects.

Strong magnetic attraction can cause magnets to accelerate together unexpectedly.

Potential hazards include:

• Pinched or trapped fingers
• Magnet collisions
• Chipping
• Cracking
• Fragmentation

Neodymium is hard but brittle despite its strong magnetic properties. Do not allow the magnet to snap uncontrolled against another magnet or steel object.

Keep permanent magnets an appropriate distance from:

• Pacemakers and implanted medical devices
• Magnetic cards
• Magnetic storage media
• Magnetically sensitive instruments
• Sensitive electronic equipment

Keep magnets securely away from children.

Please Note

This product is an N42 Neodymium Disc Magnet measuring 23.6mm in diameter x 20mm thick, manufactured from Neodymium Iron Boron (NdFeB) rare earth magnetic material.

The N42 designation identifies the magnetic material grade and does not mean the magnet has a 42kg pull force.

No specific pull force, Gauss rating, coating or plating, magnetisation direction, pole configuration, dimensional tolerance or maximum operating temperature has been supplied and these specifications should not be assumed.

Actual magnetic performance depends on the N42 material properties, magnetisation configuration, magnetic circuit, target material, target steel thickness, available contact area, surface condition, air gaps, load direction and installation geometry.

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

The stated 23.6mm diameter x 20mm thickness describes the physical geometry of the magnet and does not represent its pull force, holding capacity or safe working load.

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