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MP 25x7.5/4.5x5 / N38 - ring magnet

Name: Dhit sp. z o.o.
Address: Kościuszki 6A, Ożarów Mazowiecki, Poland, 05-850, PL
Telephone: +48 22 499 98 98
Price range: PLN 1-6500
Rating: 5

ring magnet

Catalog no 030194

GTIN/EAN: 5906301812111

5.00

Diameter

25 mm [±0,1 mm]

internal diameter Ø

7.5/4.5 mm [±0,1 mm]

Height

5 mm [±0,1 mm]

Weight

17.81 g

Magnetization Direction

↑ axial

Load capacity

7.72 kg / 75.69 N

Magnetic Induction

230.20 mT / 2302 Gs

Coating

[NiCuNi] Nickel

see technical specifications »

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Detailed specification - MP 25x7.5/4.5x5 / N38 - ring magnet

Specification / characteristics - MP 25x7.5/4.5x5 / N38 - ring magnet

properties

properties	values
Cat. no.	030194
GTIN/EAN	5906301812111
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	7.5/4.5 mm [±0,1 mm]
Height	5 mm [±0,1 mm]
Weight	17.81 g
Magnetization Direction	↑ axial
Load capacity ~ ?	7.72 kg / 75.69 N
Magnetic Induction ~ ?	230.20 mT / 2302 Gs
Coating	[NiCuNi] Nickel
Manufacturing Tolerance	±0.1 mm

Magnetic properties of material N38

Specification / characteristics MP 25x7.5/4.5x5 / N38 - ring magnet

properties	values	units
remenance Br [min. - max.] ?	12.2-12.6	kGs
remenance Br [min. - max.] ?	1220-1260	mT
coercivity bHc ?	10.8-11.5	kOe
coercivity bHc ?	860-915	kA/m
actual internal force iHc	≥ 12	kOe
actual internal force iHc	≥ 955	kA/m
energy density [min. - max.] ?	36-38	BH max MGOe
energy density [min. - max.] ?	287-303	BH max KJ/m
max. 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	312 - 380	°C
Curie Temperature TF	593 - 716	°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 analysis of the assembly - technical parameters

These values are the outcome of a mathematical analysis. Values rely on models for the class Nd₂Fe₁₄B. Real-world performance might slightly differ from theoretical values. Use these data as a reference point during assembly planning.

Table 1: Static pull force (pull vs gap) - interaction chart
MP 25x7.5/4.5x5 / N38

Distance (mm)	Induction (Gauss) / mT	Pull Force (kg/lbs/g/N)	Risk Status
0 mm	1995 Gs 199.5 mT	7.72 kg / 17.02 lbs 7720.0 g / 75.7 N	strong
1 mm	1906 Gs 190.6 mT	7.05 kg / 15.54 lbs 7049.4 g / 69.2 N	strong
2 mm	1793 Gs 179.3 mT	6.24 kg / 13.75 lbs 6236.8 g / 61.2 N	strong
3 mm	1664 Gs 166.4 mT	5.37 kg / 11.84 lbs 5368.9 g / 52.7 N	strong
5 mm	1385 Gs 138.5 mT	3.72 kg / 8.21 lbs 3722.8 g / 36.5 N	strong
10 mm	788 Gs 78.8 mT	1.20 kg / 2.65 lbs 1203.8 g / 11.8 N	safe
15 mm	437 Gs 43.7 mT	0.37 kg / 0.82 lbs 370.3 g / 3.6 N	safe
20 mm	253 Gs 25.3 mT	0.12 kg / 0.27 lbs 124.5 g / 1.2 N	safe
30 mm	101 Gs 10.1 mT	0.02 kg / 0.04 lbs 19.8 g / 0.2 N	safe
50 mm	27 Gs 2.7 mT	0.00 kg / 0.00 lbs 1.4 g / 0.0 N	safe

Magnetic force weakens sharply with every mm of spacing. Remember that even a very thin break (e.g., contamination, varnish, rust) noticeably diminishes the holding power. Neodymiums hold strongest during direct contact; gap drastically cuts the force. See how flashily the parameters drop, when the magnet does not adhere flatly to the metal substrate. When designing the assembly, eliminate additional spacers.

Table 2: Vertical capacity (wall)
MP 25x7.5/4.5x5 / N38

Distance (mm)	Friction coefficient	Pull Force (kg/lbs/g/N)
0 mm	Stal (~0.2)	1.54 kg / 3.40 lbs 1544.0 g / 15.1 N
1 mm	Stal (~0.2)	1.41 kg / 3.11 lbs 1410.0 g / 13.8 N
2 mm	Stal (~0.2)	1.25 kg / 2.75 lbs 1248.0 g / 12.2 N
3 mm	Stal (~0.2)	1.07 kg / 2.37 lbs 1074.0 g / 10.5 N
5 mm	Stal (~0.2)	0.74 kg / 1.64 lbs 744.0 g / 7.3 N
10 mm	Stal (~0.2)	0.24 kg / 0.53 lbs 240.0 g / 2.4 N
15 mm	Stal (~0.2)	0.07 kg / 0.16 lbs 74.0 g / 0.7 N
20 mm	Stal (~0.2)	0.02 kg / 0.05 lbs 24.0 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

The table below calculates the estimated shear load sufficient to cause the downward movement of the magnet downwards along a upright steel plate (assuming typical friction coefficient). The holding force varies with the distance between the magnet and the metal.

Table 3: Wall mounting (shearing) - vertical pull
MP 25x7.5/4.5x5 / N38

Surface type	Friction coefficient / % Mocy	Max load (kg/lbs/g/N)
Raw steel	µ = 0.3 30% Nominalnej Siły	2.32 kg / 5.11 lbs 2316.0 g / 22.7 N
Painted steel (standard)	µ = 0.2 20% Nominalnej Siły	1.54 kg / 3.40 lbs 1544.0 g / 15.1 N
Oily/slippery steel	µ = 0.1 10% Nominalnej Siły	0.77 kg / 1.70 lbs 772.0 g / 7.6 N
Magnet with anti-slip rubber	µ = 0.5 50% Nominalnej Siły	3.86 kg / 8.51 lbs 3860.0 g / 37.9 N

When placing a magnet on a upright surface (e.g., a fridge), it will only hold barely approx. 1/5 of its maximum pull force. Gravitational force and a low friction coefficient influence the fact that magnets move down faster than they detach. Want to create a vertical fastening? Remember that the shear force is much weaker than the perpendicular breakaway force. On a slippery surface, the magnet will slip down under a much lighter load. Using a rubber pad can effectively improve the result.

Table 4: Steel thickness (substrate influence) - power losses
MP 25x7.5/4.5x5 / N38

Steel thickness (mm)	% power	Real pull force (kg/lbs/g/N)
0.5 mm	10%	0.77 kg / 1.70 lbs 772.0 g / 7.6 N
1 mm	25%	1.93 kg / 4.25 lbs 1930.0 g / 18.9 N
2 mm	50%	3.86 kg / 8.51 lbs 3860.0 g / 37.9 N
3 mm	75%	5.79 kg / 12.76 lbs 5790.0 g / 56.8 N
5 mm	100%	7.72 kg / 17.02 lbs 7720.0 g / 75.7 N
10 mm	100%	7.72 kg / 17.02 lbs 7720.0 g / 75.7 N
11 mm	100%	7.72 kg / 17.02 lbs 7720.0 g / 75.7 N
12 mm	100%	7.72 kg / 17.02 lbs 7720.0 g / 75.7 N

A thin metal plate is unable to absorb the full magnetic flux, which weakens actual performance of the holder. If you install a neodymium to a thin surface, the magnetism will pass right through and the pull force will drop sharply. To utilize the maximum of this neodymium's power, you need a suitably thick backing of metal. The saturation effect means that on sheet metal structures (e.g., car bodies), the product holds weaker. We advise picking the steel cross-section based on the following data.

Table 5: Thermal stability (material behavior) - thermal limit
MP 25x7.5/4.5x5 / N38

Ambient temp. (°C)	Power loss	Remaining pull (kg/lbs/g/N)	Status
20 °C	0.0%	7.72 kg / 17.02 lbs 7720.0 g / 75.7 N	OK
40 °C	-2.2%	7.55 kg / 16.65 lbs 7550.2 g / 74.1 N	OK
60 °C	-4.4%	7.38 kg / 16.27 lbs 7380.3 g / 72.4 N
80 °C	-6.6%	7.21 kg / 15.90 lbs 7210.5 g / 70.7 N
100 °C	-28.8%	5.50 kg / 12.12 lbs 5496.6 g / 53.9 N

Standard neodymium magnets change their properties strength above the temperature limit. Watch out for overheating – heat can permanently destroy this magnet. As the temperature rises, the neodymium's force temporarily lowers. Avoid using this magnet close to ovens higher than its working range. Too high temperature will lead to permanent loss of magnetic properties.

*Engineering note: Temperature resistance depends not only on the material grade, and the Permeance Coefficient Pc. Flat magnets (low Pc) may lose charge permanently sooner compared to rod magnets. The danger warning in the table signals permanent field degradation for this particular item.

Table 6: Two magnets (repulsion) - field collision
MP 25x7.5/4.5x5 / N38

Gap (mm)	Attraction (kg/lbs) (N-S)	Lateral Force (kg/lbs/g/N)	Repulsion (kg/lbs) (N-N)
0 mm	9.91 kg / 21.84 lbs 3 484 Gs	1.49 kg / 3.28 lbs 1486 g / 14.6 N	N/A
1 mm	9.51 kg / 20.96 lbs 3 909 Gs	1.43 kg / 3.14 lbs 1426 g / 14.0 N	8.56 kg / 18.87 lbs ~0 Gs
2 mm	9.05 kg / 19.94 lbs 3 813 Gs	1.36 kg / 2.99 lbs 1357 g / 13.3 N	8.14 kg / 17.95 lbs ~0 Gs
3 mm	8.54 kg / 18.83 lbs 3 705 Gs	1.28 kg / 2.82 lbs 1281 g / 12.6 N	7.69 kg / 16.94 lbs ~0 Gs
5 mm	7.45 kg / 16.42 lbs 3 460 Gs	1.12 kg / 2.46 lbs 1117 g / 11.0 N	6.70 kg / 14.78 lbs ~0 Gs
10 mm	4.78 kg / 10.53 lbs 2 771 Gs	0.72 kg / 1.58 lbs 717 g / 7.0 N	4.30 kg / 9.48 lbs ~0 Gs
20 mm	1.54 kg / 3.41 lbs 1 576 Gs	0.23 kg / 0.51 lbs 232 g / 2.3 N	1.39 kg / 3.06 lbs ~0 Gs
50 mm	0.06 kg / 0.13 lbs 312 Gs	0.01 kg / 0.02 lbs 9 g / 0.1 N	0.05 kg / 0.12 lbs ~0 Gs
60 mm	0.03 kg / 0.06 lbs 202 Gs	0.00 kg / 0.01 lbs 4 g / 0.0 N	0.02 kg / 0.05 lbs ~0 Gs
70 mm	0.01 kg / 0.03 lbs 138 Gs	0.00 kg / 0.00 lbs 2 g / 0.0 N	0.01 kg / 0.02 lbs ~0 Gs
80 mm	0.01 kg / 0.01 lbs 97 Gs	0.00 kg / 0.00 lbs 1 g / 0.0 N	0.00 kg / 0.00 lbs ~0 Gs
90 mm	0.00 kg / 0.01 lbs 71 Gs	0.00 kg / 0.00 lbs 0 g / 0.0 N	0.00 kg / 0.00 lbs ~0 Gs
100 mm	0.00 kg / 0.00 lbs 54 Gs	0.00 kg / 0.00 lbs 0 g / 0.0 N	0.00 kg / 0.00 lbs ~0 Gs

Two magnets attract each other from a wider radius than a magnet and sheet setup. The connection of magnet-to-magnet generates a stronger field and a larger range of operation. Want to build a strong closure? Apply two magnets instead of one magnet and a steel. Exercise caution that when connecting a pair of magnets, the pinch force is massive. The repulsion force is a bit weaker than the attraction, but still impressive.
*Flux density for N-N configuration is approximately ~0 Gs in the exact middle of the gap (resulting from vector opposition).
Note: Estimates refer to sliding force of two same magnets (friction coefficient ~0.15 for Ni-Ni coating).

Table 7: Safety (HSE) (implants) - warnings
MP 25x7.5/4.5x5 / N38

Object / Device	Limit (Gauss) / mT	Safe distance
Pacemaker	5 Gs (0.5 mT)	9.5 cm
Hearing aid	10 Gs (1.0 mT)	7.5 cm
Mechanical watch	20 Gs (2.0 mT)	6.0 cm
Phone / Smartphone	40 Gs (4.0 mT)	4.5 cm
Remote	50 Gs (5.0 mT)	4.0 cm
Payment card	400 Gs (40.0 mT)	2.0 cm
HDD hard drive	600 Gs (60.0 mT)	1.5 cm

A strong magnetic field poses a real danger to electronics and pacemakers. These neodymiums produce a flux that disrupts operation of digital equipment. Remember: the invisible magnetic field penetrates the body and plastic. Special caution must be exercised by people with hearing aids and insulin pumps. Also at risk are: mechanical watches, car keys, speakers, and displays. Avoid contact with magnetic cards, hard drives, or sensitive navigation tools.

Table 8: Dynamics (cracking risk) - collision effects
MP 25x7.5/4.5x5 / N38

Start from (mm)	Speed (km/h)	Energy (J)
10 mm	22.95 km/h (6.38 m/s)	0.36 J
30 mm	36.43 km/h (10.12 m/s)	0.91 J
50 mm	46.96 km/h (13.04 m/s)	1.52 J
100 mm	66.40 km/h (18.44 m/s)	3.03 J

NdFeB products are delicate – a collision with steel risks their cracking. Control the attraction moment – a neodymium left loose turns into a projectile. Striking energy can trigger coating fragments or injury to skin. Hold the magnet firmly during mounting so it doesn't hit with great force against the steel surface. A collision at high speed almost guarantees destruction of the magnet. Use safety goggles when working with large magnets.

Table 9: Surface protection spec
MP 25x7.5/4.5x5 / 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)

For outdoor applications, an epoxy coating is required; standard nickel is intended for indoor use. Note the thickness of the protective layer.

Table 10: Construction data (Flux)
MP 25x7.5/4.5x5 / N38

Parameter	Value	SI Unit / Description
Magnetic Flux	9 759 Mx	97.6 µWb
P_c Coefficient	0.25	Low (Flat)

Flux value passing through the pole surface. Essential parameter when building generators as well as sensors. The P_c coefficient defines the working geometry.

Table 11: Submerged application
MP 25x7.5/4.5x5 / N38

Environment	Effective steel pull	Effect
Air (land)	7.72 kg	Standard
Water (riverbed)	8.84 kg (+1.12 kg buoyancy gain)	+14.5%

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

The magnetic field penetrates through water without any losses. Note: for permanent underwater work, we recommend magnets with an anti-corrosive (epoxy) coating.

1. Wall mount (shear)

*Note: On a vertical wall, the magnet holds just a fraction of its nominal pull.

2. Plate thickness effect

*Thin steel (e.g. 0.5mm PC case) drastically limits the holding force.

3. Temperature resistance

*For N38 material, the safety limit is 80°C.

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

chart generated for the permeance coefficient P_c (Permeance Coefficient) = 0.25

The chart above illustrates the magnetic characteristics of the material within the second quadrant of the hysteresis loop. 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.

Engineering data and GPSR

Elemental analysis

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: 030194-2026

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UMGGW 43x6 [M4] GW / N38 - magnetic holder rubber internal thread

10.46 ZŁ brutto / pcs

It is ideally suited for places where solid attachment of the magnet to the substrate is required without the risk of detachment. 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 material behaves more like porcelain than steel, so it doesn't forgive mistakes during mounting. When tightening the screw, you must maintain great sensitivity. We recommend tightening manually with a screwdriver, not an impact driver, because excessive force will cause the ring to crack. It's a good idea to use a rubber spacer under the screw head, which will cushion the stresses. Remember: cracking during assembly results from material properties, not a product defect.

Moisture can penetrate micro-cracks in the coating and cause oxidation of the magnet. Damage to the protective layer during assembly is the most common cause of rusting. If you must use it outside, paint it with anti-corrosion paint after mounting.

A screw or bolt with a thread diameter smaller than 7.5/4.5 mm fits this model. For magnets with a straight hole, a conical head can act like a wedge and burst the magnet. Aesthetic mounting requires selecting the appropriate head size.

It is a magnetic ring with a diameter of 25 mm and thickness 5 mm. The pulling force of this model is an impressive 7.72 kg, which translates to 75.69 N in newtons. The product has a [NiCuNi] coating and is made of NdFeB material. Inner hole dimension: 7.5/4.5 mm.

The poles are located on the planes with holes, not on the sides of the ring. 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.

Pros and cons of neodymium magnets.

Advantages

Besides their remarkable strength, neodymium magnets offer the following advantages:

They have stable power, and over around ten years their attraction force decreases symbolically – ~1% (according to theory),
They are extremely resistant to demagnetization induced by presence of other magnetic fields,
By covering with a reflective layer of silver, the element acquires an modern look,
The surface of neodymium magnets generates a intense magnetic field – this is one of their assets,
Through (appropriate) combination of ingredients, they can achieve high thermal strength, allowing for operation at temperatures reaching 230°C and above...
Considering the possibility of flexible forming and adaptation to unique needs, magnetic components can be manufactured in a variety of shapes and sizes, which increases their versatility,
Versatile presence in innovative solutions – they are commonly used in HDD drives, electric drive systems, advanced medical instruments, as well as modern systems.
Compactness – despite small sizes they generate large force, making them ideal for precision applications

Limitations

Disadvantages of neodymium magnets:

Brittleness is one of their disadvantages. Upon strong impact they can fracture. We advise keeping them in a special holder, which not only protects them against impacts but also increases their durability
Neodymium magnets lose force when exposed to high temperatures. After reaching 80°C, many of them experience permanent weakening of power (a factor is the shape and dimensions of the magnet). We offer magnets specially adapted to work at temperatures up to 230°C marked [AH], which are extremely resistant to heat
They oxidize in a humid environment - during use outdoors we recommend using waterproof magnets e.g. in rubber, plastic
Limited ability of producing nuts in the magnet and complex shapes - preferred is cover - magnet mounting.
Possible danger related to microscopic parts of magnets can be dangerous, in case of ingestion, which is particularly important in the context of child safety. Additionally, tiny parts of these devices can disrupt the diagnostic process medical when they are in the body.
With large orders the cost of neodymium magnets is economically unviable,

Holding force characteristics

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

The load parameter shown refers to the maximum value, recorded under ideal test conditions, namely:

using a base made of high-permeability steel, functioning as a magnetic yoke
whose thickness reaches at least 10 mm
characterized by lack of roughness
without the slightest air gap between the magnet and steel
under axial application of breakaway force (90-degree angle)
at temperature approx. 20 degrees Celsius

What influences lifting capacity in practice

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

Space between magnet and steel – even a fraction of a millimeter of separation (caused e.g. by varnish or dirt) drastically reduces the pulling force, often by half at just 0.5 mm.
Loading method – catalog parameter refers to pulling vertically. When attempting to slide, the magnet exhibits much less (typically approx. 20-30% of nominal force).
Wall thickness – the thinner the sheet, the weaker the hold. Magnetic flux passes through the material instead of converting into lifting capacity.
Material type – ideal substrate is high-permeability steel. Cast iron may generate lower lifting capacity.
Surface condition – smooth surfaces ensure maximum contact, which increases force. Rough surfaces reduce efficiency.
Thermal conditions – NdFeB sinters have a sensitivity to temperature. At higher temperatures they are weaker, and at low temperatures they can be stronger (up to a certain limit).

Lifting capacity was assessed with the use of a smooth steel plate of optimal thickness (min. 20 mm), under perpendicular detachment force, however under shearing force the lifting capacity is smaller. In addition, even a slight gap between the magnet and the plate decreases the holding force.

Precautions when working with NdFeB magnets

Operating temperature

Monitor thermal conditions. Exposing the magnet above 80 degrees Celsius will permanently weaken its properties and strength.

Physical harm

Risk of injury: The attraction force is so immense that it can result in blood blisters, crushing, and even bone fractures. Use thick gloves.

Nickel allergy

A percentage of the population experience a contact allergy to nickel, which is the typical protective layer for NdFeB magnets. Prolonged contact might lead to dermatitis. We strongly advise use safety gloves.

Pacemakers

Patients with a pacemaker should keep an absolute distance from magnets. The magnetism can interfere with the operation of the implant.

Eye protection

Protect your eyes. Magnets can explode upon violent connection, ejecting shards into the air. We recommend safety glasses.

Immense force

Exercise caution. Rare earth magnets act from a distance and snap with massive power, often quicker than you can move away.

Data carriers

Powerful magnetic fields can erase data on payment cards, HDDs, and other magnetic media. Maintain a gap of min. 10 cm.

Danger to the youngest

Neodymium magnets are not toys. Eating multiple magnets may result in them attracting across intestines, which poses a severe health hazard and requires urgent medical intervention.

Impact on smartphones

An intense magnetic field negatively affects the operation of compasses in smartphones and GPS navigation. Maintain magnets near a device to avoid breaking the sensors.

Dust is flammable

Drilling and cutting of NdFeB material carries a risk of fire risk. Neodymium dust reacts violently with oxygen and is hard to extinguish.

Attention! Learn more about hazards in the article: Magnet Safety Guide.

MP 25x7.5/4.5x5 / N38 - ring magnet

Detailed specification - MP 25x7.5/4.5x5 / N38 - ring magnet

Magnetic properties of material N38

Physical properties of sintered neodymium magnets Nd2Fe14B at 20°C

Technical analysis of the assembly - technical parameters

Table 1: Static pull force (pull vs gap) - interaction chart MP 25x7.5/4.5x5 / N38

Table 2: Vertical capacity (wall) MP 25x7.5/4.5x5 / N38

Table 3: Wall mounting (shearing) - vertical pull MP 25x7.5/4.5x5 / N38

Table 4: Steel thickness (substrate influence) - power losses MP 25x7.5/4.5x5 / N38

Table 5: Thermal stability (material behavior) - thermal limit MP 25x7.5/4.5x5 / N38

Table 6: Two magnets (repulsion) - field collision MP 25x7.5/4.5x5 / N38

Table 7: Safety (HSE) (implants) - warnings MP 25x7.5/4.5x5 / N38

Table 8: Dynamics (cracking risk) - collision effects MP 25x7.5/4.5x5 / N38

Table 9: Surface protection spec MP 25x7.5/4.5x5 / N38

Table 10: Construction data (Flux) MP 25x7.5/4.5x5 / N38

Table 11: Submerged application MP 25x7.5/4.5x5 / N38

1. Wall mount (shear)

2. Plate thickness effect

3. Temperature resistance

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

Elemental analysis

Environmental data

Pulling force

Magnetic Induction

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Pros and cons of neodymium magnets.

Advantages

Limitations

Holding force characteristics

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

What influences lifting capacity in practice

Precautions when working with NdFeB magnets

Operating temperature

Physical harm

Nickel allergy

Pacemakers

Eye protection

Immense force

Data carriers

Danger to the youngest

Impact on smartphones

Dust is flammable

Physical properties of sintered neodymium magnets Nd₂Fe₁₄B at 20°C

Table 1: Static pull force (pull vs gap) - interaction chart
MP 25x7.5/4.5x5 / N38

Table 2: Vertical capacity (wall)
MP 25x7.5/4.5x5 / N38

Table 3: Wall mounting (shearing) - vertical pull
MP 25x7.5/4.5x5 / N38

Table 4: Steel thickness (substrate influence) - power losses
MP 25x7.5/4.5x5 / N38

Table 5: Thermal stability (material behavior) - thermal limit
MP 25x7.5/4.5x5 / N38

Table 6: Two magnets (repulsion) - field collision
MP 25x7.5/4.5x5 / N38

Table 7: Safety (HSE) (implants) - warnings
MP 25x7.5/4.5x5 / N38

Table 8: Dynamics (cracking risk) - collision effects
MP 25x7.5/4.5x5 / N38

Table 9: Surface protection spec
MP 25x7.5/4.5x5 / N38

Table 10: Construction data (Flux)
MP 25x7.5/4.5x5 / N38

Table 11: Submerged application
MP 25x7.5/4.5x5 / N38