Product available Ships today (order by 14:00)

MP 25x12.5x5 / N38 - ring magnet

Name: Dhit sp. z o.o.
Address: Kościuszki 6A, Ożarów Mazowiecki, mazowieckie, 05-850, PL
Telephone: +48 22 499 98 98
Price range: 1-6500 PLN

ring magnet

Catalog no 030342

GTIN/EAN: 5906301812289

5.00

Load capacity 5.98 kg / 58.64 N Magnetic Induction 230.20 mT / 2302 Gs

Diameter: 25 mm [±0,1 mm]
internal diameter Ø: 12.5 mm [±0,1 mm]
Height: 5 mm [±0,1 mm]
Weight: 13.81 g
Magnetization Direction: ↑ axial
Coating: [NiCuNi] Nickel

How we measure these parameters — certificates and measurements

technical specifications »

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Frequently asked questions

What is the hole in a ring magnet for?

For mounting on a screw or a shaft. The bore may be cylindrical or countersunk for a screw head. The hole removes magnet volume, so a ring holds less than a disc of the same outside diameter.

What is the polarisation?

Axial as standard — poles on the flat faces of the ring. Diametrical polarisation is made to order.

What sizes are available?

Outside diameter from 5 to 62 mm from stock. To order up to 200 mm outside diameter, 180 mm bore and 40 mm height, with a lead time of 25–35 days.

Guides from the knowledge base

Engineering report for this magnet

Full PDF analysis: pull and shear force, effect of distance, temperature and plate thickness, safety distances and the demagnetization curve.

PDF report Calculator

Want to talk magnets?

Call us now +48 888 99 98 98 alternatively let us know using contact form the contact section.
Specifications and structure of a neodymium magnet can be estimated using our power calculator.

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Physical properties - MP 25x12.5x5 / N38 - ring magnet

Specification / characteristics - MP 25x12.5x5 / N38 - ring magnet

properties

properties	values
Cat. no.	030342
GTIN/EAN	5906301812289
Production/Distribution	Dhit sp. z o.o. ul. Zielona 14 05-850 Ożarów Mazowiecki PL
Country of origin	Poland / China / Germany
Customs code	85059029
Diameter	25 mm [±0,1 mm]
internal diameter Ø	12.5 mm [±0,1 mm]
Height	5 mm [±0,1 mm]
Weight	13.81 g
Magnetization Direction	↑ axial
Load capacity ~ ?	5.98 kg / 58.64 N
Magnetic Induction ~ ?	230.20 mT / 2302 Gs
Coating	[NiCuNi] Nickel
Manufacturing Tolerance	±0.1 mm

Magnetic properties of material N38

Specification / characteristics MP 25x12.5x5 / N38 - ring magnet

properties	values	units
Remanence Br ?	12.2-12.6	kGs
Remanence Br ?	1220-1260	mT
Coercivity bHc ?	10.8-11.5	kOe
Coercivity bHc ?	860-915	kA/m
Intrinsic coercivity iHc	≥ 12	kOe
Intrinsic coercivity iHc	≥ 955	kA/m
Energy product BHmax ?	36-38	BH max MGOe
Energy product BHmax ?	287-303	BH max KJ/m
Maximum working temperature ?	≤ 80	°C

Physical properties of sintered neodymium magnets Nd₂Fe₁₄B at 20°C

properties	values	units
Vickers hardness	≥550	Hv
Density	≥7.4	g/cm³
Curie Temperature TC	310	°C
Curie Temperature TF	590	°F
Specific resistance	150	μΩ⋅cm
Bending strength	250	MPa
Compressive strength	1000~1100	MPa
Thermal expansion parallel (∥) to orientation (M)	(3-4) x 10^-6	°C^-1
Thermal expansion perpendicular (⊥) to orientation (M)	-(1-3) x 10^-6	°C^-1
Young's modulus	1.7 x 10⁴	kg/mm²

Technical simulation of the assembly - report

Presented information constitute the outcome of a engineering simulation. Values rely on models for the material Nd₂Fe₁₄B. Operational parameters may differ from theoretical values. Treat these data as a preliminary roadmap during assembly planning.

Table 1: Static force (force vs distance) - interaction chart
MP 25x12.5x5 / N38

Distance (mm)	Induction (Gauss) / mT	Pull Force (kg/lbs/g/N)	Risk Status
0 mm	5777 Gs 577.7 mT	5.98 kg / 13.18 LBS 5980.0 g / 58.7 N	medium risk
1 mm	5310 Gs 531.0 mT	5.05 kg / 11.14 LBS 5051.8 g / 49.6 N	medium risk
2 mm	4846 Gs 484.6 mT	4.21 kg / 9.27 LBS 4206.8 g / 41.3 N	medium risk
3 mm	4397 Gs 439.7 mT	3.46 kg / 7.64 LBS 3464.5 g / 34.0 N	medium risk
5 mm	3576 Gs 357.6 mT	2.29 kg / 5.05 LBS 2291.1 g / 22.5 N	medium risk
10 mm	2073 Gs 207.3 mT	0.77 kg / 1.70 LBS 769.7 g / 7.6 N	weak grip
15 mm	1231 Gs 123.1 mT	0.27 kg / 0.60 LBS 271.6 g / 2.7 N	weak grip
20 mm	773 Gs 77.3 mT	0.11 kg / 0.24 LBS 106.9 g / 1.0 N	weak grip
30 mm	356 Gs 35.6 mT	0.02 kg / 0.05 LBS 22.7 g / 0.2 N	weak grip
50 mm	115 Gs 11.5 mT	0.00 kg / 0.01 LBS 2.4 g / 0.0 N	weak grip

Magnetic force drops significantly with every mm of gap. Note that even the smallest gap (e.g., contamination, varnish, rust) strongly weakens the grip. Magnetic products hold most effectively at the point of direct contact; distance kills the force. Analyze how flashily the pull force drop, when the magnet does not adhere flatly to the steel surface. When designing the assembly, discard unnecessary gaps.

Table 2: Vertical force (wall)
MP 25x12.5x5 / N38

Distance (mm)	Friction coefficient	Pull Force (kg/lbs/g/N)
0 mm	Stal (~0.2)	1.20 kg / 2.64 LBS 1196.0 g / 11.7 N
1 mm	Stal (~0.2)	1.01 kg / 2.23 LBS 1010.0 g / 9.9 N
2 mm	Stal (~0.2)	0.84 kg / 1.86 LBS 842.0 g / 8.3 N
3 mm	Stal (~0.2)	0.69 kg / 1.53 LBS 692.0 g / 6.8 N
5 mm	Stal (~0.2)	0.46 kg / 1.01 LBS 458.0 g / 4.5 N
10 mm	Stal (~0.2)	0.15 kg / 0.34 LBS 154.0 g / 1.5 N
15 mm	Stal (~0.2)	0.05 kg / 0.12 LBS 54.0 g / 0.5 N
20 mm	Stal (~0.2)	0.02 kg / 0.05 LBS 22.0 g / 0.2 N
30 mm	Stal (~0.2)	0.00 kg / 0.01 LBS 4.0 g / 0.0 N
50 mm	Stal (~0.2)	0.00 kg / 0.00 LBS 0.0 g / 0.0 N

This section calculates the approximate force necessary to cause the slippage of the magnet downwards against a vertical steel wall (assuming typical friction). This value is a function of the separation distance between the magnet and the metal.

Table 3: Vertical assembly (shearing) - vertical pull
MP 25x12.5x5 / N38

Surface type	Friction coefficient / % Mocy	Max load (kg/lbs/g/N)
Raw steel	µ = 0.3 30% Nominalnej Siły	1.79 kg / 3.96 LBS 1794.0 g / 17.6 N
Painted steel (standard)	µ = 0.2 20% Nominalnej Siły	1.20 kg / 2.64 LBS 1196.0 g / 11.7 N
Oily/slippery steel	µ = 0.1 10% Nominalnej Siły	0.60 kg / 1.32 LBS 598.0 g / 5.9 N
Magnet with anti-slip rubber	µ = 0.5 50% Nominalnej Siły	2.99 kg / 6.59 LBS 2990.0 g / 29.3 N

When placing a element on a vertical surface (e.g., a board), it will maintain only approx. 20%-30% of its maximum pull force. Gravity and a low friction coefficient cause that holders slip easier than they pop off the substrate. Planning a hanger? Remember that the sliding force is much weaker than the perpendicular breakaway force. On a painted metal, the magnet will give way down under a noticeably lighter load. Application of an anti-slip coating can effectively increase the grip.

Table 4: Material efficiency (saturation) - sheet metal selection
MP 25x12.5x5 / N38

Steel thickness (mm)	% power	Real pull force (kg/lbs/g/N)
0.5 mm	10%	0.60 kg / 1.32 LBS 598.0 g / 5.9 N
1 mm	25%	1.50 kg / 3.30 LBS 1495.0 g / 14.7 N
2 mm	50%	2.99 kg / 6.59 LBS 2990.0 g / 29.3 N
3 mm	75%	4.49 kg / 9.89 LBS 4485.0 g / 44.0 N
5 mm	100%	5.98 kg / 13.18 LBS 5980.0 g / 58.7 N
10 mm	100%	5.98 kg / 13.18 LBS 5980.0 g / 58.7 N
11 mm	100%	5.98 kg / 13.18 LBS 5980.0 g / 58.7 N
12 mm	100%	5.98 kg / 13.18 LBS 5980.0 g / 58.7 N

A too thin steel is unable to take in the entire magnetic field, which wastes potential of the holder. Should you install a neodymium to a thin surface, the field will pass right through and the holding will be smaller. To achieve the maximum of this magnet's potential, you require a sufficiently solid piece of steel. The saturation phenomenon causes that on thin elements (e.g., appliance housings), the product holds weaker. We suggest choosing the steel dimension from these parameters.

Table 5: Thermal resistance (material behavior) - resistance threshold
MP 25x12.5x5 / N38

Ambient temp. (°C)	Power loss	Remaining pull (kg/lbs/g/N)	Status
20 °C	0.0%	5.98 kg / 13.18 LBS 5980.0 g / 58.7 N	OK
40 °C	-2.2%	5.85 kg / 12.89 LBS 5848.4 g / 57.4 N	OK
60 °C	-4.4%	5.72 kg / 12.60 LBS 5716.9 g / 56.1 N	OK
80 °C	-6.6%	5.59 kg / 12.31 LBS 5585.3 g / 54.8 N
100 °C	-28.8%	4.26 kg / 9.39 LBS 4257.8 g / 41.8 N

Ordinary NdFeB products irreversibly lose parameters past the thermal threshold. Watch out for overheating – excessive heat can permanently destroy this magnet. With every degree above norm, the neodymium's power momentarily drops. Do not use this magnet in hot environments exceeding its safe range. Exceeding the critical threshold will lead to destruction of magnetic properties.

*Technical advisory: Heat tolerance depends not only on the material grade, and the Permeance Coefficient Pc. Thin magnets (pancake types) may lose charge permanently under lower heat stress than long magnets. Red status in the table indicates permanent field degradation for this particular item.

Table 6: Two magnets (attraction) - forces in the system
MP 25x12.5x5 / N38

Gap (mm)	Attraction (kg/lbs) (N-S)	Sliding Force (kg/lbs/g/N)	Repulsion (kg/lbs) (N-N)
0 mm	82.42 kg / 181.72 LBS 6 082 Gs	12.36 kg / 27.26 LBS 12364 g / 121.3 N	N/A
1 mm	75.95 kg / 167.44 LBS 11 091 Gs	11.39 kg / 25.12 LBS 11392 g / 111.8 N	68.35 kg / 150.69 LBS ~0 Gs
2 mm	69.63 kg / 153.51 LBS 10 620 Gs	10.44 kg / 23.03 LBS 10445 g / 102.5 N	62.67 kg / 138.16 LBS ~0 Gs
3 mm	63.64 kg / 140.29 LBS 10 153 Gs	9.55 kg / 21.04 LBS 9545 g / 93.6 N	57.27 kg / 126.26 LBS ~0 Gs
5 mm	52.69 kg / 116.16 LBS 9 238 Gs	7.90 kg / 17.42 LBS 7903 g / 77.5 N	47.42 kg / 104.54 LBS ~0 Gs
10 mm	31.58 kg / 69.62 LBS 7 152 Gs	4.74 kg / 10.44 LBS 4737 g / 46.5 N	28.42 kg / 62.66 LBS ~0 Gs
20 mm	10.61 kg / 23.39 LBS 4 145 Gs	1.59 kg / 3.51 LBS 1591 g / 15.6 N	9.55 kg / 21.05 LBS ~0 Gs
50 mm	0.65 kg / 1.43 LBS 1 024 Gs	0.10 kg / 0.21 LBS 97 g / 1.0 N	0.58 kg / 1.28 LBS ~0 Gs
60 mm	0.31 kg / 0.69 LBS 712 Gs	0.05 kg / 0.10 LBS 47 g / 0.5 N	0.28 kg / 0.62 LBS ~0 Gs
70 mm	0.16 kg / 0.36 LBS 514 Gs	0.02 kg / 0.05 LBS 24 g / 0.2 N	0.15 kg / 0.32 LBS ~0 Gs
80 mm	0.09 kg / 0.20 LBS 383 Gs	0.01 kg / 0.03 LBS 14 g / 0.1 N	0.08 kg / 0.18 LBS ~0 Gs
90 mm	0.05 kg / 0.12 LBS 293 Gs	0.01 kg / 0.02 LBS 8 g / 0.1 N	0.05 kg / 0.11 LBS ~0 Gs
100 mm	0.03 kg / 0.07 LBS 230 Gs	0.00 kg / 0.01 LBS 5 g / 0.0 N	0.03 kg / 0.06 LBS ~0 Gs

Two magnetic products interact from a much further distance than a magnet and sheet combination. Such a system of magnet-to-magnet generates a stronger field and a further horizon of performance. Planning to create a powerful holder? Utilize two neodymiums instead of one magnet and a steel. Remember that when bringing together two magnets, the pinch force is extreme. The levitation is marginally weaker than the connection force, but still impressive.
*Flux density between like poles reaches ~0 Gs at the midpoint of the gap (resulting from vector opposition).
Note: Estimates show sliding force of dual identical neodymium magnets (friction ~0.15 for Ni-Ni coating).

Table 7: Hazards (implants) - precautionary measures
MP 25x12.5x5 / N38

Object / Device	Limit (Gauss) / mT	Safe distance
Pacemaker	5 Gs (0.5 mT)	17.0 cm
Hearing aid	10 Gs (1.0 mT)	13.5 cm
Timepiece	20 Gs (2.0 mT)	10.5 cm
Mobile device	40 Gs (4.0 mT)	8.0 cm
Remote	50 Gs (5.0 mT)	7.5 cm
Payment card	400 Gs (40.0 mT)	3.0 cm
HDD hard drive	600 Gs (60.0 mT)	2.5 cm

Powerful magnet radiation poses a serious hazard to electronic devices as well as pacemakers. These NdFeB products generate a flux that destroys function of sensitive medical devices. Notice: the unseen radiation acts through matter and plastic. Increased vigilance must be exercised by people with cochlear implants and insulin pumps. The risk also applies to: automatic timepieces, car keys, speakers, and screens. Do not bring the product near payment cards, hard drives, or sensitive navigation tools.

Table 8: Dynamics (cracking risk) - warning
MP 25x12.5x5 / N38

Start from (mm)	Speed (km/h)	Energy (J)
10 mm	22.15 km/h (6.15 m/s)	0.26 J
30 mm	23.66 km/h (6.57 m/s)	0.30 J
50 mm	23.73 km/h (6.59 m/s)	0.30 J
100 mm	23.74 km/h (6.59 m/s)	0.30 J

Neodymium magnets are very brittle – a collision with steel causes immediate chipping. Pay attention to connection velocity – a magnet released freely becomes dangerous. Kinetic force can destroy the magnet or painful pinches to fingers. Always hold the magnet during mounting so it doesn't slam with momentum against the metal. A collision at high speed almost guarantees destruction of the magnet. Wear safety glasses when working with large magnets.

Table 9: Corrosion resistance
MP 25x12.5x5 / N38

Technical parameter	Value / Description
Coating type	[NiCuNi] Nickel
Layer structure	Nickel - Copper - Nickel
Layer thickness	10-20 µm
Salt spray test (SST) ?	24 h
Recommended environment	Indoors only (dry)

The following table defines the conditions under which this product can be safely used. The silver nickel coating also serves an aesthetic function but is not fully waterproof.

Table 10: Electrical data (Flux)
MP 25x12.5x5 / N38

Parameter	Value	SI Unit / Description
Magnetic Flux	24 536 Mx	245.4 µWb
P_c Coefficient	1.03	High (Stable)

Flux value passing through the pole surface. Essential parameter in coil applications as well as sensors. P_c value defines the working geometry.

Table 11: Hydrostatics and buoyancy
MP 25x12.5x5 / N38

Environment	Effective steel pull	Effect
Air (land)	5.98 kg	Standard
Water (riverbed)	6.85 kg (+0.87 kg buoyancy gain)	+14.5%

Corrosion warning: Standard nickel requires drying after every contact with moisture; lack of maintenance will lead to rust spots.

Contrary to myths, water does not block the magnetic field. However, remember the water resistance when pulling the rope quickly.

1. Wall mount (shear)

*Warning: On a vertical surface, the magnet holds just ~20% of its max power.

2. Steel saturation

*Thin metal sheet (e.g. computer case) significantly reduces the holding force.

3. Temperature resistance

*For N38 grade, the max working temp is 80°C.

4. Demagnetization curve and operating point (B-H)

chart generated for the permeance coefficient P_c (Permeance Coefficient) = 1.03

This simulation demonstrates the magnetic stability of the selected magnet under specific geometric conditions. The solid red line represents the demagnetization curve (material potential), while the dashed blue line is the load line based on the magnet's geometry. The P_c (Permeance Coefficient), also known as the load line slope, is a dimensionless value that describes the relationship between the magnet's shape and its magnetic stability. The intersection of these two lines (the black dot) is the operating point — it determines the actual magnetic flux density generated by the magnet in this specific configuration. A higher P_c value means the magnet is more 'slender' (tall relative to its area), resulting in a higher operating point and better resistance to irreversible demagnetization caused by external fields or temperature. A value of 0.42 is relatively low (typical for flat magnets), meaning the operating point is closer to the 'knee' of the curve — caution is advised when operating at temperatures near the maximum limit to avoid strength loss.

Technical and environmental data

Material specification

iron (Fe)	64% – 68%
neodymium (Nd)	29% – 32%
boron (B)	1.1% – 1.2%
dysprosium (Dy)	0.5% – 2.0%
coating (Ni-Cu-Ni)	< 0.05%

Environmental data

recyclability (EoL)	100%
recycled raw materials	~10% (pre-cons)
carbon footprint	low / zredukowany
waste code (EWC)	16 02 16

Safety card (GPSR)

responsible entity

Dhit sp. z o.o.

ul. Kościuszki 6A, 05-850 Ożarów Mazowiecki

tel: +48 22 499 98 98 | e-mail: bok@dhit.pl

batch number/type

id: 030342-2026

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The ring magnet with a hole MP 25x12.5x5 / N38 is created for mechanical fastening, where glue might fail or be insufficient. Thanks to the hole (often for a screw), this model enables quick installation to wood, wall, plastic, or metal. It is also often used in advertising for fixing signs and in workshops for organizing tools.

This is a crucial issue when working with model MP 25x12.5x5 / N38. Neodymium magnets are sintered ceramics, which means they are very brittle and inelastic. When tightening the screw, you must maintain caution. We recommend tightening manually with a screwdriver, not an impact driver, because excessive force will cause the ring to crack. The flat screw head should evenly press the magnet. Remember: cracking during assembly results from material properties, not a product defect.

These magnets are coated with standard Ni-Cu-Ni plating, which protects them in indoor conditions, but does not ensure full waterproofing. In the place of the mounting hole, the coating is thinner and easily scratched when tightening the screw, which will become a corrosion focus. This product is dedicated for indoor use. For outdoor applications, we recommend choosing magnets in hermetic housing or additional protection with varnish.

The inner hole diameter determines the maximum size of the mounting element. If the magnet does not have a chamfer (cone), we recommend using a screw with a flat or cylindrical head, or possibly using a washer. Always check that the screw head is not larger than the outer diameter of the magnet (25 mm), so it doesn't protrude beyond the outline.

The presented product is a ring magnet with dimensions Ø25 mm (outer diameter) and height 5 mm. The pulling force of this model is an impressive 5.98 kg, which translates to 58.64 N in newtons. The mounting hole diameter is precisely 12.5 mm.

These magnets are magnetized axially (through the thickness), which means one flat side is the N pole and the other is S. If you want two such magnets screwed with cones facing each other (faces) to attract, you must connect them with opposite poles (N to S). When ordering a larger quantity, magnets are usually packed in stacks, where they are already naturally paired.

Advantages as well as disadvantages of Nd₂Fe₁₄B magnets.

Benefits

In addition to their magnetic efficiency, neodymium magnets provide the following advantages:

Their magnetic field is durable, and after approximately ten years it decreases only by ~1% (according to research),
They do not lose their magnetic properties even under close interference source,
A magnet with a shiny silver surface has an effective appearance,
They are known for high magnetic induction at the operating surface, which affects their effectiveness,
Due to their durability and thermal resistance, neodymium magnets can operate (depending on the form) even at high temperatures reaching 230°C or more...
Thanks to flexibility in constructing and the ability to customize to individual projects,
Huge importance in modern industrial fields – they find application in data components, electric drive systems, medical equipment, as well as technologically advanced constructions.
Relatively small size with high pulling force – neodymium magnets offer strong magnetic field in tiny dimensions, which makes them useful in compact constructions

Cons

Disadvantages of neodymium magnets:

At strong impacts they can crack, therefore we recommend placing them in special holders. A metal housing provides additional protection against damage, as well as increases the magnet's durability.
When exposed to high temperature, neodymium magnets suffer a drop in power. Often, when the temperature exceeds 80°C, their strength decreases (depending on the size and shape of the magnet). For those who need magnets for extreme conditions, we offer [AH] versions withstanding up to 230°C
Magnets exposed to a humid environment can corrode. Therefore during using outdoors, we recommend using water-impermeable magnets made of rubber, plastic or other material protecting against moisture
Due to limitations in producing threads and complex shapes in magnets, we propose using casing - magnetic mount.
Potential hazard resulting from small fragments of magnets can be dangerous, when accidentally swallowed, which is particularly important in the aspect of protecting the youngest. Additionally, small components of these products can be problematic in diagnostics medical when they are in the body.
Due to complex production process, their price exceeds standard values,

Holding force characteristics

Optimal lifting capacity of a neodymium magnet – what affects it?

The load parameter shown concerns the maximum value, recorded under optimal environment, namely:

on a base made of mild steel, optimally conducting the magnetic field
with a cross-section no less than 10 mm
with an ideally smooth contact surface
without any insulating layer between the magnet and steel
during pulling in a direction vertical to the plane
at conditions approx. 20°C

Impact of factors on magnetic holding capacity in practice

Please note that the working load will differ subject to the following factors, starting with the most relevant:

Distance – the presence of foreign body (paint, dirt, air) acts as an insulator, which lowers power steeply (even by 50% at 0.5 mm).
Pull-off angle – remember that the magnet holds strongest perpendicularly. Under shear forces, the holding force drops drastically, often to levels of 20-30% of the nominal value.
Wall thickness – thin material does not allow full use of the magnet. Part of the magnetic field penetrates through instead of converting into lifting capacity.
Metal type – different alloys attracts identically. Alloy additives worsen the interaction with the magnet.
Base smoothness – the smoother and more polished the plate, the better the adhesion and stronger the hold. Unevenness creates an air distance.
Thermal factor – high temperature weakens pulling force. Exceeding the limit temperature can permanently damage the magnet.

Lifting capacity was assessed using a polished steel plate of optimal thickness (min. 20 mm), under vertically applied force, however under shearing force the lifting capacity is smaller. Additionally, even a small distance between the magnet and the plate lowers the load capacity.

Safety rules for work with NdFeB magnets

Caution required

Use magnets with awareness. Their immense force can surprise even professionals. Stay alert and respect their power.

Finger safety

Danger of trauma: The attraction force is so immense that it can result in hematomas, crushing, and broken bones. Protective gloves are recommended.

Product not for children

These products are not intended for children. Accidental ingestion of a few magnets may result in them pinching intestinal walls, which poses a severe health hazard and necessitates urgent medical intervention.

Threat to electronics

Device Safety: Strong magnets can damage data carriers and sensitive devices (heart implants, hearing aids, mechanical watches).

Life threat

Patients with a heart stimulator have to maintain an absolute distance from magnets. The magnetic field can stop the operation of the life-saving device.

Protective goggles

NdFeB magnets are ceramic materials, which means they are prone to chipping. Clashing of two magnets will cause them shattering into shards.

Dust is flammable

Powder created during cutting of magnets is flammable. Do not drill into magnets without proper cooling and knowledge.

Precision electronics

Navigation devices and smartphones are extremely susceptible to magnetic fields. Close proximity with a powerful NdFeB magnet can permanently damage the internal compass in your phone.

Heat sensitivity

Watch the temperature. Exposing the magnet above 80 degrees Celsius will destroy its magnetic structure and strength.

Sensitization to coating

Studies show that the nickel plating (standard magnet coating) is a potent allergen. If your skin reacts to metals, prevent direct skin contact and choose coated magnets.

Safety First! Need more info? Check our post: Are neodymium magnets dangerous?

MP 25x12.5x5 / N38 - ring magnet

Physical properties - MP 25x12.5x5 / N38 - ring magnet

Magnetic properties of material N38

Physical properties of sintered neodymium magnets Nd2Fe14B at 20°C

Technical simulation of the assembly - report

Table 1: Static force (force vs distance) - interaction chart MP 25x12.5x5 / N38

Table 2: Vertical force (wall) MP 25x12.5x5 / N38

Table 3: Vertical assembly (shearing) - vertical pull MP 25x12.5x5 / N38

Table 4: Material efficiency (saturation) - sheet metal selection MP 25x12.5x5 / N38

Table 5: Thermal resistance (material behavior) - resistance threshold MP 25x12.5x5 / N38

Table 6: Two magnets (attraction) - forces in the system MP 25x12.5x5 / N38

Table 7: Hazards (implants) - precautionary measures MP 25x12.5x5 / N38

Table 8: Dynamics (cracking risk) - warning MP 25x12.5x5 / N38

Table 9: Corrosion resistance MP 25x12.5x5 / N38

Table 10: Electrical data (Flux) MP 25x12.5x5 / N38

Table 11: Hydrostatics and buoyancy MP 25x12.5x5 / N38

1. Wall mount (shear)

2. Steel saturation

3. Temperature resistance

4. Demagnetization curve and operating point (B-H)

Material specification

Environmental data

Force (pull)

Magnetic Field

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Advantages as well as disadvantages of Nd2Fe14B magnets.

Benefits

Cons

Holding force characteristics

Optimal lifting capacity of a neodymium magnet – what affects it?

Impact of factors on magnetic holding capacity in practice

Safety rules for work with NdFeB magnets

Caution required

Finger safety

Product not for children

Threat to electronics

Life threat

Protective goggles

Dust is flammable

Precision electronics

Heat sensitivity

Sensitization to coating

Physical properties of sintered neodymium magnets Nd₂Fe₁₄B at 20°C

Table 1: Static force (force vs distance) - interaction chart
MP 25x12.5x5 / N38

Table 2: Vertical force (wall)
MP 25x12.5x5 / N38

Table 3: Vertical assembly (shearing) - vertical pull
MP 25x12.5x5 / N38

Table 4: Material efficiency (saturation) - sheet metal selection
MP 25x12.5x5 / N38

Table 5: Thermal resistance (material behavior) - resistance threshold
MP 25x12.5x5 / N38

Table 6: Two magnets (attraction) - forces in the system
MP 25x12.5x5 / N38

Table 7: Hazards (implants) - precautionary measures
MP 25x12.5x5 / N38

Table 8: Dynamics (cracking risk) - warning
MP 25x12.5x5 / N38

Table 9: Corrosion resistance
MP 25x12.5x5 / N38

Table 10: Electrical data (Flux)
MP 25x12.5x5 / N38

Table 11: Hydrostatics and buoyancy
MP 25x12.5x5 / N38

Advantages as well as disadvantages of Nd₂Fe₁₄B magnets.