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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

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Technical specification of the product - 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

Engineering modeling of the magnet - technical parameters

Presented data constitute the outcome of a engineering calculation. Results rely on models for the class Nd₂Fe₁₄B. Real-world conditions might slightly differ from theoretical values. Please consider these calculations as a supplementary guide for designers.

Table 1: Static force (force vs gap) - characteristics
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 pounds 4140.0 g / 40.6 N	warning
1 mm	5310 Gs 531.0 mT	3.50 kg / 7.71 pounds 3497.4 g / 34.3 N	warning
2 mm	4846 Gs 484.6 mT	2.91 kg / 6.42 pounds 2912.4 g / 28.6 N	warning
3 mm	4397 Gs 439.7 mT	2.40 kg / 5.29 pounds 2398.5 g / 23.5 N	warning
5 mm	3576 Gs 357.6 mT	1.59 kg / 3.50 pounds 1586.2 g / 15.6 N	weak grip
10 mm	2073 Gs 207.3 mT	0.53 kg / 1.17 pounds 532.9 g / 5.2 N	weak grip
15 mm	1231 Gs 123.1 mT	0.19 kg / 0.41 pounds 188.0 g / 1.8 N	weak grip
20 mm	773 Gs 77.3 mT	0.07 kg / 0.16 pounds 74.0 g / 0.7 N	weak grip
30 mm	356 Gs 35.6 mT	0.02 kg / 0.03 pounds 15.7 g / 0.2 N	weak grip
50 mm	115 Gs 11.5 mT	0.00 kg / 0.00 pounds 1.6 g / 0.0 N	weak grip

Pulling power drops drastically with every subsequent millimeter of spacing. Remember that every additional insulation layer (e.g., dirt, varnish, dust) significantly weakens the grip. Magnets hold most effectively during direct contact; distance kills the force. Notice how quickly the parameters fall, when the product does not adhere directly to the metal substrate. When planning the mounting, avoid redundant distances.

Table 2: Sliding load (wall)
MP 25x13x4 / N38

Distance (mm)	Friction coefficient	Pull Force (kg/lbs/g/N)
0 mm	Stal (~0.2)	0.83 kg / 1.83 pounds 828.0 g / 8.1 N
1 mm	Stal (~0.2)	0.70 kg / 1.54 pounds 700.0 g / 6.9 N
2 mm	Stal (~0.2)	0.58 kg / 1.28 pounds 582.0 g / 5.7 N
3 mm	Stal (~0.2)	0.48 kg / 1.06 pounds 480.0 g / 4.7 N
5 mm	Stal (~0.2)	0.32 kg / 0.70 pounds 318.0 g / 3.1 N
10 mm	Stal (~0.2)	0.11 kg / 0.23 pounds 106.0 g / 1.0 N
15 mm	Stal (~0.2)	0.04 kg / 0.08 pounds 38.0 g / 0.4 N
20 mm	Stal (~0.2)	0.01 kg / 0.03 pounds 14.0 g / 0.1 N
30 mm	Stal (~0.2)	0.00 kg / 0.01 pounds 4.0 g / 0.0 N
50 mm	Stal (~0.2)	0.00 kg / 0.00 pounds 0.0 g / 0.0 N

This section indicates the approximate force required to start the shifting of the magnet down on a upright metal surface (considering standard friction). The holding force varies with the gap size between the magnet and the metal.

Table 3: Vertical assembly (sliding) - behavior on slippery surfaces
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 pounds 1242.0 g / 12.2 N
Painted steel (standard)	µ = 0.2 20% Nominalnej Siły	0.83 kg / 1.83 pounds 828.0 g / 8.1 N
Oily/slippery steel	µ = 0.1 10% Nominalnej Siły	0.41 kg / 0.91 pounds 414.0 g / 4.1 N
Magnet with anti-slip rubber	µ = 0.5 50% Nominalnej Siły	2.07 kg / 4.56 pounds 2070.0 g / 20.3 N

When mounting a magnet on a upright wall (e.g., a car body), it will maintain only approx. 1/5 of nominal attraction strength. Gravity as well as a low friction coefficient cause that magnets move down faster than they pull off. Want to create a wall mount? Consider that the shear force is noticeably lower than the perpendicular breakaway force. On a smooth steel, the element will give way down under a significantly smaller weight. Using a rubber pad can significantly improve the result.

Table 4: Steel thickness (substrate influence) - sheet metal selection
MP 25x13x4 / N38

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

A too thin steel is unable to take in the entire magnetic field, which squanders power of the holder. If you attach a powerful product to a too thin substrate, the flux will pass right through and the holding will be smaller. To utilize the maximum of this magnet's potential, you require a sufficiently solid piece of metal. The material oversaturation causes that on sheet metal structures (e.g., appliance housings), the holder shows lower pull force. We recommend selecting the steel cross-section according to the table below.

Table 5: Thermal resistance (stability) - power drop
MP 25x13x4 / N38

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

Classic neodymiums lose strength above the temperature limit. Protect against heat – excessive heat can irreversibly destroy this product. As the temperature rises, the magnet's force momentarily drops. Avoid using this magnet near heat sources exceeding its working range. Ignoring the limit will lead to destruction of magnetism.

*Technical advisory: Heat tolerance depends not only on the material grade, and the Permeance Coefficient Pc. Flat magnets (low Pc) risk losing magnetic properties at lower temperatures than long magnets. The danger warning in the table indicates permanent field degradation for this particular item.

Table 6: Magnet-Magnet interaction (repulsion) - 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 pounds 6 082 Gs	12.55 kg / 27.67 pounds 12549 g / 123.1 N	N/A
1 mm	77.09 kg / 169.95 pounds 11 091 Gs	11.56 kg / 25.49 pounds 11563 g / 113.4 N	69.38 kg / 152.95 pounds ~0 Gs
2 mm	70.68 kg / 155.81 pounds 10 620 Gs	10.60 kg / 23.37 pounds 10601 g / 104.0 N	63.61 kg / 140.23 pounds ~0 Gs
3 mm	64.59 kg / 142.40 pounds 10 153 Gs	9.69 kg / 21.36 pounds 9689 g / 95.0 N	58.13 kg / 128.16 pounds ~0 Gs
5 mm	53.48 kg / 117.90 pounds 9 238 Gs	8.02 kg / 17.68 pounds 8022 g / 78.7 N	48.13 kg / 106.11 pounds ~0 Gs
10 mm	32.05 kg / 70.66 pounds 7 152 Gs	4.81 kg / 10.60 pounds 4808 g / 47.2 N	28.85 kg / 63.60 pounds ~0 Gs
20 mm	10.77 kg / 23.74 pounds 4 145 Gs	1.62 kg / 3.56 pounds 1615 g / 15.8 N	9.69 kg / 21.37 pounds ~0 Gs
50 mm	0.66 kg / 1.45 pounds 1 024 Gs	0.10 kg / 0.22 pounds 99 g / 1.0 N	0.59 kg / 1.30 pounds ~0 Gs
60 mm	0.32 kg / 0.70 pounds 712 Gs	0.05 kg / 0.10 pounds 48 g / 0.5 N	0.29 kg / 0.63 pounds ~0 Gs
70 mm	0.17 kg / 0.36 pounds 514 Gs	0.02 kg / 0.05 pounds 25 g / 0.2 N	0.15 kg / 0.33 pounds ~0 Gs
80 mm	0.09 kg / 0.20 pounds 383 Gs	0.01 kg / 0.03 pounds 14 g / 0.1 N	0.08 kg / 0.18 pounds ~0 Gs
90 mm	0.05 kg / 0.12 pounds 293 Gs	0.01 kg / 0.02 pounds 8 g / 0.1 N	0.05 kg / 0.11 pounds ~0 Gs
100 mm	0.03 kg / 0.07 pounds 230 Gs	0.00 kg / 0.01 pounds 5 g / 0.0 N	0.03 kg / 0.07 pounds ~0 Gs

Two magnetic products attract each other from a much further distance than a magnet and sheet setup. The setup of two magnets generates a stronger field and a further horizon of operation. Planning to create a powerful holder? Use a pair of magnets instead of one magnet and a steel. Remember that when attracting two neodymiums, the pinch force is massive. The repulsion force is slightly lower than the attraction, but still significant.
*Field value for N-N configuration drops to ~0 Gs at the midpoint of the gap (caused by magnetic field nullification).
Important: Calculations apply to shear force of a pair of identical magnets (friction coefficient ~0.15 for Ni-Ni plating).

Table 7: Hazards (electronics) - precautionary measures
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
Phone / Smartphone	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

A strong magnetic field poses a serious hazard to IT equipment as well as medical implants. These neodymiums generate a flux that disrupts operation of digital equipment. Remember: the invisible magnetic field passes through tissues and glass. Special caution must be exercised by people with cochlear implants and insulin pumps. Also at risk are: automatic timepieces, remotes, speakers, and displays. Do not bring the product near payment cards, hard drives, or precise measuring instruments.

Table 8: Dynamics (kinetic energy) - collision effects
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

Neodymium magnets are very brittle – a violent impact against metal causes immediate chipping. Pay attention to connection velocity – a neodymium left loose becomes dangerous. Striking energy can destroy the magnet or injury to skin. Always hold the magnet during bringing near metal so it doesn't slam with momentum against the metal. A contact at a velocity of dozens of km/h means shattering of the neodymium. 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. The silver nickel coating also serves an aesthetic function but is not fully waterproof.

Table 10: Construction data (P_c)
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 passing through the pole surface. Key data in coil applications as well as sensors. The P_c coefficient determines the working geometry.

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%

Rust risk: 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 retains only ~20% of its nominal pull.

2. Efficiency vs thickness

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

3. Thermal stability

*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) = 1.02

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 specification and ecology

Chemical composition

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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The ring magnet with a hole MP 25x13x4 / N38 is created for permanent mounting, where glue might fail or be insufficient. Mounting is clean and reversible, unlike gluing. 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. One turn too many can destroy the magnet, so do it slowly. It's a good idea to use a flexible washer 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. In the place of the mounting hole, the coating is thinner and can be damaged 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. 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.

This model is characterized by dimensions Ø25x4 mm and a weight of 10.74 g. The pulling force of this model is an impressive 4.14 kg, which translates to 40.57 N in newtons. The mounting hole diameter is precisely 13 mm.

These magnets are magnetized axially (through the thickness), which means one flat side is the N pole and the other is S. In the case of connecting two rings, make sure one is turned the right way. When ordering a larger quantity, magnets are usually packed in stacks, where they are already naturally paired.

Pros and cons of neodymium magnets.

Pros

Besides their durability, neodymium magnets are valued for these benefits:

Their strength is maintained, and after around 10 years it drops only by ~1% (according to research),
They do not lose their magnetic properties even under external field action,
By covering with a lustrous layer of nickel, the element presents an modern look,
Magnets possess maximum magnetic induction on the working surface,
Neodymium magnets are characterized by very high magnetic induction on the magnet surface and are able to act (depending on the form) even at a temperature of 230°C or more...
Possibility of custom forming and adapting to concrete conditions,
Versatile presence in electronics industry – they find application in hard drives, electric motors, advanced medical instruments, and multitasking production systems.
Thanks to concentrated force, small magnets offer high operating force, occupying minimum space,

Cons

Disadvantages of NdFeB magnets:

To avoid cracks upon strong impacts, we suggest using special steel housings. Such a solution secures the magnet and simultaneously increases its durability.
We warn that neodymium magnets can reduce their power at high temperatures. To prevent this, we suggest our specialized [AH] magnets, which work effectively even at 230°C.
Magnets exposed to a humid environment can corrode. Therefore when using outdoors, we suggest using waterproof magnets made of rubber, plastic or other material resistant to moisture
Limited ability of producing threads in the magnet and complicated forms - preferred is casing - magnet mounting.
Health risk resulting from small fragments of magnets pose a threat, when accidentally swallowed, which is particularly important in the aspect of protecting the youngest. Additionally, small elements of these magnets are able to complicate diagnosis medical when they are in the body.
Due to expensive raw materials, their price is relatively high,

Pull force analysis

Maximum magnetic pulling force – what affects it?

The lifting capacity listed is a theoretical maximum value executed under the following configuration:

with the contact of a sheet made of low-carbon steel, ensuring full magnetic saturation
possessing a massiveness of at least 10 mm to ensure full flux closure
characterized by lack of roughness
without any insulating layer between the magnet and steel
under axial force vector (90-degree angle)
in stable room temperature

Practical lifting capacity: influencing factors

In real-world applications, the actual lifting capacity depends on a number of factors, listed from crucial:

Clearance – the presence of any layer (paint, tape, gap) acts as an insulator, which reduces capacity steeply (even by 50% at 0.5 mm).
Force direction – note that the magnet has greatest strength perpendicularly. Under shear forces, the holding force drops significantly, often to levels of 20-30% of the nominal value.
Steel thickness – insufficiently thick sheet causes magnetic saturation, causing part of the power to be wasted to the other side.
Steel grade – ideal substrate is pure iron steel. Cast iron may generate lower lifting capacity.
Surface quality – the more even the surface, the larger the contact zone and higher the lifting capacity. Unevenness acts like micro-gaps.
Temperature – temperature increase results in weakening of force. It is worth remembering the thermal limit for a given model.

Lifting capacity testing was carried out on plates with a smooth surface of optimal thickness, under a perpendicular pulling force, whereas under shearing force the load capacity is reduced by as much as 5 times. Additionally, even a slight gap between the magnet and the plate reduces the holding force.

Precautions when working with neodymium magnets

Serious injuries

Watch your fingers. Two powerful magnets will snap together instantly with a force of several hundred kilograms, destroying everything in their path. Exercise extreme caution!

Protective goggles

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

Safe operation

Handle magnets consciously. Their huge power can surprise even experienced users. Stay alert and respect their power.

Flammability

Dust created during machining of magnets is self-igniting. Avoid drilling into magnets without proper cooling and knowledge.

Health Danger

People with a heart stimulator must maintain an safe separation from magnets. The magnetism can stop the functioning of the implant.

Power loss in heat

Regular neodymium magnets (grade N) lose magnetization when the temperature goes above 80°C. This process is irreversible.

Precision electronics

Be aware: neodymium magnets generate a field that disrupts sensitive sensors. Maintain a safe distance from your phone, device, and GPS.

Skin irritation risks

Some people experience a contact allergy to nickel, which is the standard coating for neodymium magnets. Frequent touching might lead to dermatitis. It is best to use protective gloves.

Electronic hazard

Device Safety: Neodymium magnets can ruin data carriers and delicate electronics (pacemakers, hearing aids, mechanical watches).

Danger to the youngest

Always store magnets out of reach of children. Ingestion danger is high, and the consequences of magnets clamping inside the body are tragic.

Attention! Looking for details? Read our article: Why are neodymium magnets dangerous?

MP 25x13x4 / N38 - ring magnet

Technical specification of the product - MP 25x13x4 / N38 - ring magnet

Magnetic properties of material N38

Physical properties of sintered neodymium magnets Nd2Fe14B at 20°C

Engineering modeling of the magnet - technical parameters

Table 1: Static force (force vs gap) - characteristics MP 25x13x4 / N38

Table 2: Sliding load (wall) MP 25x13x4 / N38

Table 3: Vertical assembly (sliding) - behavior on slippery surfaces MP 25x13x4 / N38

Table 4: Steel thickness (substrate influence) - sheet metal selection MP 25x13x4 / N38

Table 5: Thermal resistance (stability) - power drop MP 25x13x4 / N38

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

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

Table 8: Dynamics (kinetic energy) - collision effects MP 25x13x4 / N38

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

Table 10: Construction data (Pc) MP 25x13x4 / N38

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

1. Wall mount (shear)

2. Efficiency vs thickness

3. Thermal stability

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

Chemical composition

Sustainability

Pulling force

Field Strength

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Pros and cons of neodymium magnets.

Pros

Cons

Pull force analysis

Maximum magnetic pulling force – what affects it?

Practical lifting capacity: influencing factors

Precautions when working with neodymium magnets

Serious injuries

Protective goggles

Safe operation

Flammability

Health Danger

Power loss in heat

Precision electronics

Skin irritation risks

Electronic hazard

Danger to the youngest

Physical properties of sintered neodymium magnets Nd₂Fe₁₄B at 20°C

Table 1: Static force (force vs gap) - characteristics
MP 25x13x4 / N38

Table 2: Sliding load (wall)
MP 25x13x4 / N38

Table 3: Vertical assembly (sliding) - behavior on slippery surfaces
MP 25x13x4 / N38

Table 4: Steel thickness (substrate influence) - sheet metal selection
MP 25x13x4 / N38

Table 5: Thermal resistance (stability) - power drop
MP 25x13x4 / N38

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

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

Table 8: Dynamics (kinetic energy) - collision effects
MP 25x13x4 / N38

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

Table 10: Construction data (P_c)
MP 25x13x4 / N38

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