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MP 25x13x4 / 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 030190

GTIN/EAN: 5906301812074

5.00

Diameter

25 mm [±0,1 mm]

internal diameter Ø

13 mm [±0,1 mm]

Height

4 mm [±0,1 mm]

Weight

10.74 g

Magnetization Direction

↑ axial

Load capacity

4.14 kg / 40.57 N

Magnetic Induction

188.92 mT / 1889 Gs

Coating

[NiCuNi] Nickel

view specifications »

6.77 ZŁ with VAT / pcs + price for transport

5.50 ZŁ net + 23% VAT / pcs

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Force and appearance of a neodymium magnet can be calculated with our our magnetic calculator.

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Technical details - MP 25x13x4 / N38 - ring magnet

Specification / characteristics - MP 25x13x4 / N38 - ring magnet

properties

properties	values
Cat. no.	030190
GTIN/EAN	5906301812074
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	13 mm [±0,1 mm]
Height	4 mm [±0,1 mm]
Weight	10.74 g
Magnetization Direction	↑ axial
Load capacity ~ ?	4.14 kg / 40.57 N
Magnetic Induction ~ ?	188.92 mT / 1889 Gs
Coating	[NiCuNi] Nickel
Manufacturing Tolerance	±0.1 mm

Magnetic properties of material N38

Specification / characteristics MP 25x13x4 / 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 product - data

Presented data represent the outcome of a physical analysis. Values are based on algorithms for the material Nd₂Fe₁₄B. Actual conditions might slightly deviate from the simulation results. Please consider these calculations as a reference point during assembly planning.

Table 1: Static pull force (force vs gap) - power drop
MP 25x13x4 / N38

Distance (mm)	Induction (Gauss) / mT	Pull Force (kg/lbs/g/N)	Risk Status
0 mm	5777 Gs 577.7 mT	4.14 kg / 9.13 LBS 4140.0 g / 40.6 N	warning
1 mm	5310 Gs 531.0 mT	3.50 kg / 7.71 LBS 3497.4 g / 34.3 N	warning
2 mm	4846 Gs 484.6 mT	2.91 kg / 6.42 LBS 2912.4 g / 28.6 N	warning
3 mm	4397 Gs 439.7 mT	2.40 kg / 5.29 LBS 2398.5 g / 23.5 N	warning
5 mm	3576 Gs 357.6 mT	1.59 kg / 3.50 LBS 1586.2 g / 15.6 N	weak grip
10 mm	2073 Gs 207.3 mT	0.53 kg / 1.17 LBS 532.9 g / 5.2 N	weak grip
15 mm	1231 Gs 123.1 mT	0.19 kg / 0.41 LBS 188.0 g / 1.8 N	weak grip
20 mm	773 Gs 77.3 mT	0.07 kg / 0.16 LBS 74.0 g / 0.7 N	weak grip
30 mm	356 Gs 35.6 mT	0.02 kg / 0.03 LBS 15.7 g / 0.2 N	weak grip
50 mm	115 Gs 11.5 mT	0.00 kg / 0.00 LBS 1.6 g / 0.0 N	weak grip

Grip strength decreases drastically with every subsequent millimeter of gap. Note that even the smallest gap (e.g., dirt, paint, rust) significantly diminishes the holding power. Magnetic products hold most effectively during direct contact; distance weakens the force. Analyze how flashily the load capacity fall, when the magnet does not adhere tightly to the steel surface. When calculating the mounting, eliminate redundant distances.

Table 2: Vertical force (wall)
MP 25x13x4 / N38

Distance (mm)	Friction coefficient	Pull Force (kg/lbs/g/N)
0 mm	Stal (~0.2)	0.83 kg / 1.83 LBS 828.0 g / 8.1 N
1 mm	Stal (~0.2)	0.70 kg / 1.54 LBS 700.0 g / 6.9 N
2 mm	Stal (~0.2)	0.58 kg / 1.28 LBS 582.0 g / 5.7 N
3 mm	Stal (~0.2)	0.48 kg / 1.06 LBS 480.0 g / 4.7 N
5 mm	Stal (~0.2)	0.32 kg / 0.70 LBS 318.0 g / 3.1 N
10 mm	Stal (~0.2)	0.11 kg / 0.23 LBS 106.0 g / 1.0 N
15 mm	Stal (~0.2)	0.04 kg / 0.08 LBS 38.0 g / 0.4 N
20 mm	Stal (~0.2)	0.01 kg / 0.03 LBS 14.0 g / 0.1 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 shows the estimated force required to initiate the downward movement of the magnet vertically against a vertical steel wall (considering typical friction coefficient). The holding force depends on the gap size between the magnet and the surface.

Table 3: Wall mounting (shearing) - vertical pull
MP 25x13x4 / N38

Surface type	Friction coefficient / % Mocy	Max load (kg/lbs/g/N)
Raw steel	µ = 0.3 30% Nominalnej Siły	1.24 kg / 2.74 LBS 1242.0 g / 12.2 N
Painted steel (standard)	µ = 0.2 20% Nominalnej Siły	0.83 kg / 1.83 LBS 828.0 g / 8.1 N
Oily/slippery steel	µ = 0.1 10% Nominalnej Siły	0.41 kg / 0.91 LBS 414.0 g / 4.1 N
Magnet with anti-slip rubber	µ = 0.5 50% Nominalnej Siły	2.07 kg / 4.56 LBS 2070.0 g / 20.3 N

When placing a magnet on a upright wall (e.g., a fridge), it you can count on just about 20%-30% of its nominal power. Gravitational force as well as a weak degree of grip mean that products slide down faster than they detach. Want to create a vertical fastening? Note that the shear force is noticeably lower than the perpendicular breakaway force. On a smooth steel, the holder will slide down under a much lighter weight. Utilizing a rubberized pad can significantly improve the result.

Table 4: Material efficiency (substrate influence) - power losses
MP 25x13x4 / N38

Steel thickness (mm)	% power	Real pull force (kg/lbs/g/N)
0.5 mm	10%	0.41 kg / 0.91 LBS 414.0 g / 4.1 N
1 mm	25%	1.04 kg / 2.28 LBS 1035.0 g / 10.2 N
2 mm	50%	2.07 kg / 4.56 LBS 2070.0 g / 20.3 N
3 mm	75%	3.10 kg / 6.85 LBS 3105.0 g / 30.5 N
5 mm	100%	4.14 kg / 9.13 LBS 4140.0 g / 40.6 N
10 mm	100%	4.14 kg / 9.13 LBS 4140.0 g / 40.6 N
11 mm	100%	4.14 kg / 9.13 LBS 4140.0 g / 40.6 N
12 mm	100%	4.14 kg / 9.13 LBS 4140.0 g / 40.6 N

A thin sheet cannot take in the entire magnetic field, which weakens actual performance of the holder. If you install a neodymium to a weak sheet, the field will penetrate right through and the attraction force will be weaker. To achieve the maximum of this magnet's power, you need a suitably thick backing of metal. The saturation phenomenon means that on delicate walls (e.g., car bodies), the holder shows lower pull force. We recommend selecting the steel thickness from these parameters.

Table 5: Thermal resistance (material behavior) - thermal limit
MP 25x13x4 / N38

Ambient temp. (°C)	Power loss	Remaining pull (kg/lbs/g/N)	Status
20 °C	0.0%	4.14 kg / 9.13 LBS 4140.0 g / 40.6 N	OK
40 °C	-2.2%	4.05 kg / 8.93 LBS 4048.9 g / 39.7 N	OK
60 °C	-4.4%	3.96 kg / 8.73 LBS 3957.8 g / 38.8 N	OK
80 °C	-6.6%	3.87 kg / 8.52 LBS 3866.8 g / 37.9 N
100 °C	-28.8%	2.95 kg / 6.50 LBS 2947.7 g / 28.9 N

Ordinary NdFeB products irreversibly lose power after exceeding the maximum temperature. Protect against heat – excessive heat can permanently damage this product. As the temperature rises, the neodymium's capacity momentarily drops. Avoid using this magnet near heat sources exceeding its working range. Ignoring the limit will cause permanent loss of magnetism.

*Important note: Thermal stability is determined by both grade, but also on the magnet's shape. Flat magnets (pancake types) are more susceptible to demagnetization at lower temperatures than taller cylinders. Red status in the table points to a risk of irreversible loss for this particular item.

Table 6: Magnet-Magnet interaction (attraction) - forces in the system
MP 25x13x4 / N38

Gap (mm)	Attraction (kg/lbs) (N-S)	Sliding Force (kg/lbs/g/N)	Repulsion (kg/lbs) (N-N)
0 mm	83.66 kg / 184.44 LBS 6 082 Gs	12.55 kg / 27.67 LBS 12549 g / 123.1 N	N/A
1 mm	77.09 kg / 169.95 LBS 11 091 Gs	11.56 kg / 25.49 LBS 11563 g / 113.4 N	69.38 kg / 152.95 LBS ~0 Gs
2 mm	70.68 kg / 155.81 LBS 10 620 Gs	10.60 kg / 23.37 LBS 10601 g / 104.0 N	63.61 kg / 140.23 LBS ~0 Gs
3 mm	64.59 kg / 142.40 LBS 10 153 Gs	9.69 kg / 21.36 LBS 9689 g / 95.0 N	58.13 kg / 128.16 LBS ~0 Gs
5 mm	53.48 kg / 117.90 LBS 9 238 Gs	8.02 kg / 17.68 LBS 8022 g / 78.7 N	48.13 kg / 106.11 LBS ~0 Gs
10 mm	32.05 kg / 70.66 LBS 7 152 Gs	4.81 kg / 10.60 LBS 4808 g / 47.2 N	28.85 kg / 63.60 LBS ~0 Gs
20 mm	10.77 kg / 23.74 LBS 4 145 Gs	1.62 kg / 3.56 LBS 1615 g / 15.8 N	9.69 kg / 21.37 LBS ~0 Gs
50 mm	0.66 kg / 1.45 LBS 1 024 Gs	0.10 kg / 0.22 LBS 99 g / 1.0 N	0.59 kg / 1.30 LBS ~0 Gs
60 mm	0.32 kg / 0.70 LBS 712 Gs	0.05 kg / 0.10 LBS 48 g / 0.5 N	0.29 kg / 0.63 LBS ~0 Gs
70 mm	0.17 kg / 0.36 LBS 514 Gs	0.02 kg / 0.05 LBS 25 g / 0.2 N	0.15 kg / 0.33 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 / 0.07 LBS ~0 Gs

Two magnetic products attract each other from a much further distance than a neodymium and metal setup. Such a system of two magnets produces a massive flux and a wider radius of performance. Planning to create a strong closure? Apply two magnets instead of one magnet and a striker plate. Exercise caution that when connecting a pair of magnets, the collision energy is huge. The repulsion force is marginally weaker than the connection force, but still large.
*Field value in repulsion mode drops to ~0 Gs at the midpoint between the magnets (due to field cancellation).
Important: Results demonstrate friction force of dual identical magnets (friction coefficient ~0.15 for Ni-Ni coating).

Table 7: Hazards (electronics) - warnings
MP 25x13x4 / 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
Car key	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

Extremely neodym field is a serious hazard to IT equipment and pacemakers. These magnets generate a field that disrupts operation of sensitive medical devices. Notice: the unseen radiation passes through tissues and glass. Special caution must be taken by people with hearing aids and drug dispensers. Also at risk are: mechanical watches, remotes, membranes, and screens. Do not bring the product near payment cards, hard drives, or sensitive navigation tools.

Table 8: Impact energy (kinetic energy) - warning
MP 25x13x4 / N38

Start from (mm)	Speed (km/h)	Energy (J)
10 mm	21.33 km/h (5.93 m/s)	0.19 J
30 mm	34.38 km/h (9.55 m/s)	0.49 J
50 mm	44.29 km/h (12.30 m/s)	0.81 J
100 mm	62.62 km/h (17.39 m/s)	1.62 J

NdFeB products are very brittle – a collision with steel causes immediate chipping. Pay attention to connection velocity – a neodymium left loose speeds with massive force. Impact energy can cause material chips or dangerous crushing to fingers. Be sure to control the product during mounting so it doesn't hit with great force against the steel surface. A contact at a velocity of dozens of km/h ends with a crack of the magnet. Use safety goggles when handling with large magnets.

Table 9: Anti-corrosion coating durability
MP 25x13x4 / 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. Improper coating selection is the most common cause of magnet failure over time.

Table 10: Electrical data (Flux)
MP 25x13x4 / N38

Parameter	Value	SI Unit / Description
Magnetic Flux	24 861 Mx	248.6 µWb
P_c Coefficient	1.02	High (Stable)

Flux value emitted by the pole surface. Key data when building generators as well as sensors. The P_c coefficient defines the magnet's operating point.

Table 11: Underwater work (magnet fishing)
MP 25x13x4 / N38

Environment	Effective steel pull	Effect
Air (land)	4.14 kg	Standard
Water (riverbed)	4.74 kg (+0.60 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. Buoyancy helps in lifting finds.

1. Sliding resistance

*Caution: On a vertical surface, the magnet holds merely a fraction of its perpendicular strength.

2. Steel saturation

*Thin metal sheet (e.g. 0.5mm PC case) severely weakens the holding force.

3. Heat tolerance

*For standard magnets, the critical limit is 80°C.

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

chart generated for the permeance coefficient P_c (Permeance Coefficient) = 1.02

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%

Sustainability

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: 030190-2026

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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 easy screwing 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 25x13x4 / N38. Neodymium magnets are sintered ceramics, which means they are hard but breakable 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.

Moisture can penetrate micro-cracks in the coating and cause oxidation of the magnet. In the place of the mounting hole, the coating is thinner and easily scratched when tightening the screw, which will become a corrosion focus. If you must use it outside, paint it with anti-corrosion paint after mounting.

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. Aesthetic mounting requires selecting the appropriate head size.

The presented product is a ring magnet with dimensions Ø25 mm (outer diameter) and height 4 mm. The key parameter here is the lifting capacity amounting to approximately 4.14 kg (force ~40.57 N). The product has a [NiCuNi] coating and is made of NdFeB material. Inner hole dimension: 13 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). We do not offer paired sets with marked poles in this category, but they are easy to match manually.

Pros as well as cons of rare earth magnets.

Benefits

Apart from their strong magnetism, neodymium magnets have these key benefits:

They have unchanged lifting capacity, and over more than 10 years their performance decreases symbolically – ~1% (in testing),
Neodymium magnets prove to be extremely resistant to loss of magnetic properties caused by external interference,
Thanks to the reflective finish, the plating of nickel, gold-plated, or silver-plated gives an aesthetic appearance,
The surface of neodymium magnets generates a unique magnetic field – this is a key feature,
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 freedom in forming and the ability to adapt to complex applications,
Wide application in modern industrial fields – they find application in magnetic memories, drive modules, medical equipment, as well as other advanced devices.
Thanks to their power density, small magnets offer high operating force, with minimal size,

Limitations

Drawbacks and weaknesses of neodymium magnets and ways of using them

Brittleness is one of their disadvantages. Upon strong impact they can break. We advise keeping them in a steel housing, which not only secures them against impacts but also raises their durability
When exposed to high temperature, neodymium magnets experience 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
When exposed to humidity, magnets start to rust. For applications outside, it is recommended to use protective magnets, such as those in rubber or plastics, which secure oxidation and corrosion.
We suggest cover - magnetic mount, due to difficulties in producing nuts inside the magnet and complex shapes.
Health risk related to microscopic parts of magnets can be dangerous, when accidentally swallowed, which is particularly important in the aspect of protecting the youngest. Furthermore, small elements of these products can disrupt the diagnostic process medical in case of swallowing.
Due to expensive raw materials, their price exceeds standard values,

Lifting parameters

Maximum lifting capacity of the magnet – what affects it?

Holding force of 4.14 kg is a theoretical maximum value executed under standard conditions:

with the contact of a sheet made of low-carbon steel, guaranteeing full magnetic saturation
possessing a thickness of min. 10 mm to avoid saturation
characterized by even structure
without any clearance between the magnet and steel
under vertical application of breakaway force (90-degree angle)
at room temperature

Practical lifting capacity: influencing factors

In real-world applications, the actual holding force depends on several key aspects, presented from most significant:

Air gap (betwixt the magnet and the plate), because even a very small clearance (e.g. 0.5 mm) leads to a drastic drop in force by up to 50% (this also applies to paint, rust or dirt).
Pull-off angle – note that the magnet holds strongest perpendicularly. Under shear forces, the holding force drops drastically, often to levels of 20-30% of the nominal value.
Base massiveness – too thin sheet does not close the flux, causing part of the power to be wasted to the other side.
Material composition – not every steel reacts the same. Alloy additives worsen the attraction effect.
Surface condition – smooth surfaces guarantee perfect abutment, which improves field saturation. Uneven metal reduce efficiency.
Temperature – temperature increase results in weakening of induction. Check the thermal limit for a given model.

Lifting capacity testing was performed on plates with a smooth surface of optimal thickness, under a perpendicular pulling force, however under parallel forces the holding force is lower. In addition, even a small distance between the magnet’s surface and the plate reduces the holding force.

Precautions when working with NdFeB magnets

Magnets are brittle

Despite metallic appearance, neodymium is brittle and not impact-resistant. Avoid impacts, as the magnet may crumble into sharp, dangerous pieces.

Crushing risk

Danger of trauma: The pulling power is so great that it can result in blood blisters, pinching, and even bone fractures. Use thick gloves.

Demagnetization risk

Monitor thermal conditions. Exposing the magnet to high heat will permanently weaken its magnetic structure and pulling force.

Nickel coating and allergies

Nickel alert: The nickel-copper-nickel coating consists of nickel. If an allergic reaction occurs, cease working with magnets and wear gloves.

Handling rules

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

Threat to navigation

A strong magnetic field interferes with the functioning of magnetometers in phones and navigation systems. Keep magnets near a smartphone to prevent breaking the sensors.

Dust explosion hazard

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

Keep away from children

Neodymium magnets are not suitable for play. Swallowing several magnets can lead to them attracting across intestines, which poses a critical condition and requires urgent medical intervention.

Medical implants

Medical warning: Strong magnets can deactivate heart devices and defibrillators. Stay away if you have medical devices.

Keep away from computers

Equipment safety: Strong magnets can damage data carriers and delicate electronics (heart implants, hearing aids, mechanical watches).

Warning! Want to know more? Check our post: Are neodymium magnets dangerous?

MP 25x13x4 / N38 - ring magnet

Technical details - MP 25x13x4 / N38 - ring magnet

Magnetic properties of material N38

Physical properties of sintered neodymium magnets Nd2Fe14B at 20°C

Technical analysis of the product - data

Table 1: Static pull force (force vs gap) - power drop MP 25x13x4 / N38

Table 2: Vertical force (wall) MP 25x13x4 / N38

Table 3: Wall mounting (shearing) - vertical pull MP 25x13x4 / N38

Table 4: Material efficiency (substrate influence) - power losses MP 25x13x4 / N38

Table 5: Thermal resistance (material behavior) - thermal limit MP 25x13x4 / N38

Table 6: Magnet-Magnet interaction (attraction) - forces in the system MP 25x13x4 / N38

Table 7: Hazards (electronics) - warnings MP 25x13x4 / N38

Table 8: Impact energy (kinetic energy) - warning MP 25x13x4 / N38

Table 9: Anti-corrosion coating durability MP 25x13x4 / N38

Table 10: Electrical data (Flux) MP 25x13x4 / N38

Table 11: Underwater work (magnet fishing) MP 25x13x4 / N38

1. Sliding resistance

2. Steel saturation

3. Heat tolerance

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

Elemental analysis

Sustainability

Magnet pull force

Field Strength

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MW 6x3 / N38 - cylindrical magnet

Pros as well as cons of rare earth magnets.

Benefits

Limitations

Lifting parameters

Maximum lifting capacity of the magnet – what affects it?

Practical lifting capacity: influencing factors

Precautions when working with NdFeB magnets

Magnets are brittle

Crushing risk

Demagnetization risk

Nickel coating and allergies

Handling rules

Threat to navigation

Dust explosion hazard

Keep away from children

Medical implants

Keep away from computers

Physical properties of sintered neodymium magnets Nd₂Fe₁₄B at 20°C

Table 1: Static pull force (force vs gap) - power drop
MP 25x13x4 / N38

Table 2: Vertical force (wall)
MP 25x13x4 / N38

Table 3: Wall mounting (shearing) - vertical pull
MP 25x13x4 / N38

Table 4: Material efficiency (substrate influence) - power losses
MP 25x13x4 / N38

Table 5: Thermal resistance (material behavior) - thermal limit
MP 25x13x4 / N38

Table 6: Magnet-Magnet interaction (attraction) - forces in the system
MP 25x13x4 / N38

Table 7: Hazards (electronics) - warnings
MP 25x13x4 / N38

Table 8: Impact energy (kinetic energy) - warning
MP 25x13x4 / N38

Table 9: Anti-corrosion coating durability
MP 25x13x4 / N38

Table 10: Electrical data (Flux)
MP 25x13x4 / N38

Table 11: Underwater work (magnet fishing)
MP 25x13x4 / N38