Neodymium Block Magnet – 75mm x 20mm x 5mm with Hole D10mm | N45

The Neodymium Block Magnet – 75mm x 20mm x 5mm with Hole D10mm | N45 is a long, low-profile rare earth permanent magnet measuring 75mm long x 20mm wide x 5mm thick, with a 10mm diameter hole incorporated into the block. Manufactured from N45 grade Neodymium Iron Boron (NdFeB), this rectangular magnet combines strong magnetic performance with a practical through-hole design for integration into engineered products, fixtures, positioning systems, equipment and custom magnetic assemblies.

Its 75mm x 20mm rectangular footprint provides an elongated magnetic form while the slim 5mm thickness helps minimise installation depth. The 10mm diameter hole provides a useful mechanical integration point where the magnet needs to be located, retained or incorporated around a compatible component.

This magnet is suitable for engineering, manufacturing, fixtures and jigs, product assemblies, positioning, alignment, machinery, equipment, research, prototyping and OEM applications where a rectangular N45 rare earth magnet with a central opening is required.

Also known as an N45 neodymium block magnet with hole, rare earth rectangular magnet, NdFeB bar magnet with through-hole, 75mm neodymium block magnet or rectangular mounting magnet, it provides permanent magnetic operation without electricity, batteries or charging.

Key Features

• Length: 75mm
• Width: 20mm
• Thickness: 5mm
• Dimensions: 75mm x 20mm x 5mm
• Hole diameter: 10mm
• Shape: Rectangular block / bar
• Material: Neodymium Iron Boron (NdFeB)
• Magnetic grade: N45
• Magnet type: Rare earth permanent magnet
• Long, low-profile rectangular geometry
• Slim 5mm thickness
• Integrated 10mm diameter hole
• Strong magnetic performance relative to size
• Suitable for engineering and manufacturing
• Useful for fixtures, jigs and positioning systems
• Suitable for mechanical and product assemblies
• Useful for research and prototype development
• Suitable for custom OEM magnetic systems
• Permanent magnetic operation
• No electricity, batteries or charging required

Common Applications

• Engineering
• Manufacturing
• Industrial equipment
• Machinery
• Product assemblies
• Fixtures and jigs
• Magnetic positioning
• Component alignment
• Equipment housings
• Removable components
• Mechanical assemblies
• Custom magnetic systems
• Research and development
• Laboratory equipment
• Prototype devices
• OEM products

75mm x 20mm x 5mm Rectangular Neodymium Magnet

This N45 neodymium block magnet measures:

• 75mm long
• 20mm wide
• 5mm thick

The elongated rectangular geometry provides a length-to-width ratio of approximately 3.75:1, while the 5mm thickness creates a relatively low-profile magnetic component.

This geometry can be useful where a magnet needs to fit within:

• Long rectangular recesses
• Equipment housings
• Machinery
• Fixtures
• Product assemblies
• Custom brackets
• Prototype mechanisms

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

Integrated 10mm Diameter Hole

This neodymium block magnet includes a 10mm diameter hole.

The hole can provide a useful integration point in appropriately designed mechanical and magnetic assemblies.

Potential functions include:

• Locating the magnet around a compatible component
• Providing clearance for another assembly component
• Incorporating the magnet into custom fixtures
• Mechanical positioning
• Product integration
• Prototype assembly

The 10mm hole diameter should not automatically be interpreted as compatibility with a 10mm bolt, shaft, pin or other component. Actual fit depends on the dimensions and tolerances of both components and the clearance required by the application.

Through-Hole vs Countersunk Hole

The supplied product information specifies a 10mm diameter hole, but does not identify the hole as countersunk, counterbored or threaded.

Unless separately confirmed, it should therefore not be assumed to have:

• A countersunk recess
• A counterbore
• An internal thread
• A particular screw-head profile
• Compatibility with a specific fastener

If the magnet is being selected for a mounting application, confirm the actual hole geometry and required hardware before installation.

N45 Grade Neodymium Magnet

This block magnet is manufactured from N45 grade Neodymium Iron Boron.

N45 is a high-performance rare earth magnetic grade that provides substantial magnetic energy from relatively compact dimensions.

N45 neodymium magnets are useful where:

• Strong permanent magnetic performance is required
• Available installation space is limited
• A relatively thin magnet is preferred
• High magnetic energy density is desirable
• A specific rectangular geometry is required

The N45 designation identifies the magnetic material grade and does not indicate a 45kg pull force.

What Does N45 Mean?

N45 is a classification of the Neodymium Iron Boron magnetic material used to manufacture this magnet.

The numerical grade relates to the material's maximum energy product and is used to differentiate the magnetic performance potential of different NdFeB grades.

When magnets have equivalent dimensions, geometry and magnetisation configuration, higher numerical neodymium grades can generally provide greater magnetic performance than lower grades.

However, N45 does not directly specify:

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

These characteristics depend on the finished magnet and the complete magnetic circuit.

Strong Rare Earth Magnetic Material

Neodymium Iron Boron is a high-performance rare earth permanent magnetic material widely used in industrial and engineered products.

Its high magnetic energy density allows substantial magnetic performance to be produced from relatively compact magnet dimensions.

Potential functions for this 75mm block magnet include:

• Magnetic attraction
• Holding
• Positioning
• Alignment
• Component retention
• Product integration
• Magnetic coupling

The suitability of the magnet for any specific function depends on the complete application and magnetic circuit.

Fixtures and Jigs

The elongated rectangular profile can make this N45 block magnet useful for appropriately designed fixtures and jigs.

Potential applications include:

• Component positioning
• Assembly aids
• Repeatable locating
• Inspection fixtures
• Alignment systems
• Prototype tooling

The 10mm hole may also provide additional integration options within a custom fixture.

Magnetic attraction should not replace appropriate mechanical clamping or retention where unexpected movement could create a safety hazard.

Positioning and Alignment

This N45 block magnet may be incorporated into magnetic positioning and alignment systems.

Potential functions include:

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

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

Magnetisation Direction

Rectangular neodymium magnets can be manufactured with different magnetisation configurations.

A 75mm x 20mm x 5mm block magnet could potentially be magnetised:

• Through its 5mm thickness
• Across its 20mm width
• Along its 75mm length
• In another specialised configuration

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

Confirm this specification where pole position or magnetic field orientation is important.

Magnetic Performance

Although this magnet is confirmed as N45 grade, practical magnetic performance depends on multiple factors.

These include:

• N45 material properties
• Magnetisation direction
• Pole configuration
• Hole geometry
• Magnetic circuit design
• Target steel composition
• Target steel thickness
• Available contact area
• Surface condition
• Air gaps
• Load direction
• Mechanical leverage
• Installation geometry

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

These values should not be estimated from the N45 designation or magnet dimensions alone.

N45 Does Not Mean 45kg Pull Force

The N45 designation does not mean this magnet has a 45kg pull force.

N45 identifies the grade of the Neodymium Iron Boron magnetic material.

Pull force is a separate performance measurement affected by:

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

Use a verified pull-force specification where magnetic holding capacity is important.

Direct Pull vs Shear Force

Magnetic holding performance changes depending on the direction in which a load is applied.

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 surface.

Shear performance can be influenced by:

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

Testing under realistic installation conditions is recommended where holding performance is important.

Air Gaps and Magnetic Attraction

Air gaps can significantly reduce the practical magnetic 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 magnetic working surface and target should generally be minimised.

Target Steel Thickness

Where this magnet operates against ferromagnetic steel, the target material forms part of the magnetic circuit.

Performance can be influenced by:

• 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.

Installing a Neodymium Block Magnet with a Hole

The 10mm hole may provide useful options for incorporating the magnet into a mechanical assembly, but care is required because neodymium is a hard and brittle magnetic material.

Before installation:

• Confirm the hole geometry
• Confirm component or fastener compatibility
• Confirm magnetisation direction
• Confirm polarity where multiple magnets are used
• Provide appropriate mechanical clearance
• Avoid force-fitting
• Avoid point loading around the hole
• Avoid excessive clamping pressure
• Ensure the magnet is adequately supported

If a mechanical component passes through the hole, it should not place excessive radial or clamping force on the brittle magnet.

Avoid Overtightening

Neodymium magnets can fracture when subjected to excessive mechanical pressure.

If the 10mm hole is used as part of a mechanical mounting system, avoid overtightening hardware directly against the magnet.

Excessive pressure can cause:

• Cracking around the hole
• Chipping
• Fracturing
• Surface damage
• Complete magnet failure

Where appropriate, use a mounting design that distributes mechanical loads rather than concentrating them around the hole.

Bonding the Magnet

Bonding may also be used as part of the installation method.

Before bonding:

• Confirm magnetic polarity and orientation
• Clean both bonding surfaces
• Remove dust, grease and contamination
• Select an adhesive compatible with the actual magnet surface
• 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 finish should be confirmed.

Do Not Machine Neodymium Magnets

The existing 10mm hole should not be enlarged or modified using conventional workshop methods.

Avoid:

• Drilling
• Reaming
• Cutting
• Grinding
• Crushing
• Machining

Neodymium is brittle, and machining can damage both the magnetic material and any protective surface coating.

If another hole diameter or magnet size is required, select a magnet manufactured to the required 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 can also be weakly magnetic or non-magnetic and should be tested before relying on magnetic attraction.

N45 Neodymium vs Ferrite Block Magnets

N45 neodymium and ferrite block magnets provide different performance characteristics.

N45 neodymium magnets generally provide:

• Higher magnetic performance relative to size
• High magnetic energy density
• Strong performance from compact dimensions
• Advantages where installation space is restricted

Ferrite magnets generally provide:

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

N45 neodymium is commonly selected where strong magnetic performance from a relatively compact permanent magnet is required.

Permanent Magnetic Operation

This N45 neodymium block 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 Block Magnet – 75mm x 20mm x 5mm with Hole D10mm | N45
• Product Type: Neodymium Block Magnet with Hole
• Alternative Names: N45 Neodymium Block Magnet with Hole, Rare Earth Block Magnet, NdFeB Bar Magnet with Hole, Rectangular Neodymium Magnet, Rare Earth Rectangular Magnet
• Length: 75mm
• Width: 20mm
• Thickness: 5mm
• Dimensions: 75mm x 20mm x 5mm
• Hole Diameter: 10mm
• Shape: Rectangular Block / Bar
• Magnetic Material: Neodymium Iron Boron (NdFeB)
• Magnetic Grade: N45
• 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 and product integration
• Typical Applications: Engineering, manufacturing, machinery, fixtures, jigs, equipment, product assemblies, prototypes and OEM magnetic systems

Safety and Handling

This N45 neodymium block magnet should be handled carefully around other magnets and ferromagnetic objects.

Strong magnetic attraction can cause magnets or steel objects to accelerate together unexpectedly.

Potential hazards include:

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

The slim 5mm profile and presence of a 10mm hole can create areas that are vulnerable to mechanical stress. Avoid bending, twisting, impact and concentrated loading around the hole.

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 N45 Neodymium Block Magnet measuring 75mm long x 20mm wide x 5mm thick with a 10mm diameter hole, manufactured from Neodymium Iron Boron (NdFeB) rare earth magnetic material.

The supplied information identifies a 10mm diameter hole, but does not specify whether the hole is countersunk, counterbored, threaded or designed for a particular fastener. A 10mm hole should not automatically be interpreted as compatibility with a 10mm bolt, shaft or pin.

The N45 designation identifies the magnetic material grade and does not mean the magnet has a 45kg pull force.

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

Actual magnetic performance depends on the N45 material properties, magnetisation configuration, magnetic circuit, target material, target steel thickness, available contact area, surface condition, air gaps, load direction, mechanical leverage and installation geometry.

Neodymium is a hard and brittle magnetic material. Avoid impact, bending, force-fitting, overtightening, drilling, cutting, grinding or machining, particularly around the 10mm hole.

The stated 75mm x 20mm x 5mm dimensions and 10mm hole describe the physical geometry of the magnet and do 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.