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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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6.77 ZŁ with VAT / pcs + price for transport

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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 simulation of the magnet - data

The following values represent the outcome of a engineering analysis. Values are based on algorithms for the class Nd₂Fe₁₄B. Real-world parameters might slightly differ from theoretical values. Treat these data as a reference point for designers.

Table 1: Static force (pull 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 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	safe
10 mm	2073 Gs 207.3 mT	0.53 kg / 1.17 LBS 532.9 g / 5.2 N	safe
15 mm	1231 Gs 123.1 mT	0.19 kg / 0.41 LBS 188.0 g / 1.8 N	safe
20 mm	773 Gs 77.3 mT	0.07 kg / 0.16 LBS 74.0 g / 0.7 N	safe
30 mm	356 Gs 35.6 mT	0.02 kg / 0.03 LBS 15.7 g / 0.2 N	safe
50 mm	115 Gs 11.5 mT	0.00 kg / 0.00 LBS 1.6 g / 0.0 N	safe

Magnetic force drops sharply with every subsequent millimeter of gap. Remember that every additional insulation layer (e.g., dirt, paint, dust) significantly weakens the grip. Neodymiums work optimally during direct contact; gap weakens the power. Observe how quickly the pull force drop, when the magnet does not touch tightly to the metal substrate. When planning the mounting, discard unnecessary gaps.

Table 2: Shear load (vertical surface)
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

The table below shows the approximate holding capacity needed to start the slippage of the magnet vertically on a vertical steel plate (assuming typical friction). This value is a function of the gap size between the magnet and the surface.

Table 3: Wall mounting (sliding) - 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 mounting a element on a upright wall (e.g., a car body), it will maintain only approx. 20%-30% of its nominal power. Gravitational force and a weak degree of grip mean that products slide down easier than they pop off the substrate. Planning a wall mount? Consider that the shear force is significantly lower than the perpendicular breakaway force. On a painted metal, the magnet will slip down under a much lighter weight. Using a rubber coating can effectively improve the result.

Table 4: Material efficiency (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 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 absorb the full magnetic flux, which wastes potential of the holder. If you mount a strong magnet to a weak sheet, the magnetism will pass right through and the attraction force will be weaker. To squeeze 100% of this magnet's potential, you need a suitably thick piece of steel. The saturation effect causes that on thin elements (e.g., appliance housings), the magnet works worse. We advise picking the steel thickness from these parameters.

Table 5: Working in heat (material behavior) - 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 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

Standard neodymium magnets lose parameters past the thermal threshold. Watch out for overheating – heat can permanently damage this product. As the temperature rises, the magnet's power momentarily lowers. Do not use this magnet close to ovens higher than its operating temperature limit. Exceeding the critical threshold will result in destruction of magnetism.

*Technical advisory: Heat tolerance is determined by both grade, but also on the magnet's shape. Flat magnets (pancake types) may lose charge permanently at lower temperatures compared to rod magnets. Warning indicator in the table indicates a risk of irreversible loss for this particular item.

Table 6: Magnet-Magnet interaction (repulsion) - field range
MP 25x13x4 / N38

Gap (mm)	Attraction (kg/lbs) (N-S)	Lateral 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 magnets interact from a wider radius than a magnet and steel setup. The connection of two magnets generates a stronger field and a larger range of performance. Designing a powerful holder? Use a pair of magnets instead of a neodymium and a striker plate. Exercise caution that when bringing together two magnets, the pinch force is extreme. The levitation is marginally weaker than the attraction, but still impressive.
*Field value between like poles reaches ~0 Gs at the midpoint of the gap (due to field cancellation).
* Figures demonstrate shear force of dual same magnets (friction coefficient ~0.15 for Ni-Ni layer).

Table 7: Protective zones (implants) - 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
Mechanical watch	20 Gs (2.0 mT)	10.5 cm
Phone / Smartphone	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

Powerful magnet radiation poses a serious hazard to electronic devices as well as medical implants. These NdFeB products generate a flux that prevents correct functioning of digital equipment. Be aware: the invisible magnetic field acts through matter and plastic. Exceptional care must be taken by people with hearing aids and drug dispensers. Influence will be felt by: automatic timepieces, car keys, speakers, and displays. Avoid contact with magnetic cards, hard drives, or sensitive navigation tools.

Table 8: Dynamics (cracking risk) - 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

NdFeB products are delicate – a violent impact against metal can result in shattering. Watch the impact speed – a magnet released freely turns into a projectile. Kinetic force can trigger coating fragments or dangerous crushing to skin. Always hold the magnet during installation so it doesn't hit violently against the steel surface. A contact at a velocity of dozens of km/h means shattering of the magnet. Use safety goggles when working with large magnets.

Table 9: Corrosion resistance
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: 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. P_c value determines the magnet's operating point.

Table 11: Physics of underwater searching
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: Remember to wipe the magnet thoroughly after removing it from water and apply a protective layer (e.g., oil) to avoid corrosion.

Water displaces steel, making heavy objects slightly lighter. Note: for permanent underwater work, we recommend magnets with an anti-corrosive (epoxy) coating.

1. Sliding resistance

*Warning: On a vertical surface, the magnet retains only approx. 20-30% of its nominal pull.

2. Steel saturation

*Thin steel (e.g. 0.5mm PC case) significantly weakens the holding force.

3. Power loss vs temp

*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) = 1.02

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.

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

Measurement Calculator

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Force in kg

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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 quick installation to wood, wall, plastic, or metal. This product with a force of 4.14 kg works great as a door latch, speaker holder, or spacer element in devices.

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. One turn too many can destroy the magnet, so do it slowly. 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. 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.

This model is characterized by dimensions Ø25x4 mm and a weight of 10.74 g. 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.

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 as well as cons of neodymium magnets.

Strengths

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

They do not lose magnetism, even during nearly 10 years – the drop in strength is only ~1% (theoretically),
They show high resistance to demagnetization induced by external magnetic fields,
Thanks to the reflective finish, the coating of nickel, gold, or silver-plated gives an modern appearance,
Magnets are characterized by maximum magnetic induction on the outer layer,
Neodymium magnets are characterized by extremely high magnetic induction on the magnet surface and can work (depending on the shape) even at a temperature of 230°C or more...
Possibility of individual creating and modifying to individual conditions,
Wide application in modern technologies – they are used in data components, electromotive mechanisms, diagnostic systems, as well as multitasking production systems.
Relatively small size with high pulling force – neodymium magnets offer high power in compact dimensions, which makes them useful in compact constructions

Weaknesses

Cons of neodymium magnets: weaknesses and usage proposals

To avoid cracks upon strong impacts, we suggest using special steel holders. Such a solution secures the magnet and simultaneously increases its durability.
Neodymium magnets demagnetize 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 very resistant to heat
They rust in a humid environment. For use outdoors we suggest using waterproof magnets e.g. in rubber, plastic
We suggest cover - magnetic holder, due to difficulties in realizing threads inside the magnet and complex shapes.
Potential hazard to health – tiny shards of magnets are risky, in case of ingestion, which becomes key in the context of child health protection. Furthermore, small components of these devices can complicate diagnosis medical when they are in the body.
With budget limitations the cost of neodymium magnets is economically unviable,

Pull force analysis

Maximum lifting force for a neodymium magnet – what contributes to it?

Information about lifting capacity is the result of a measurement for the most favorable conditions, assuming:

with the use of a sheet made of low-carbon steel, ensuring maximum field concentration
possessing a thickness of at least 10 mm to ensure full flux closure
with an ideally smooth contact surface
under conditions of ideal adhesion (surface-to-surface)
for force acting at a right angle (in the magnet axis)
at conditions approx. 20°C

Determinants of practical lifting force of a magnet

In real-world applications, the real power results from many variables, listed from the most important:

Distance – existence of any layer (rust, dirt, gap) interrupts the magnetic circuit, which lowers capacity rapidly (even by 50% at 0.5 mm).
Force direction – note that the magnet has greatest strength perpendicularly. Under shear forces, the capacity drops drastically, often to levels of 20-30% of the maximum value.
Base massiveness – too thin sheet does not accept the full field, causing part of the flux to be lost to the other side.
Steel type – low-carbon steel attracts best. Alloy admixtures decrease magnetic properties and holding force.
Surface quality – the smoother and more polished the plate, the better the adhesion and stronger the hold. Roughness acts like micro-gaps.
Thermal factor – high temperature reduces pulling force. Exceeding the limit temperature can permanently damage the magnet.

Lifting capacity testing was performed on a smooth plate of suitable thickness, under perpendicular forces, in contrast under shearing force the holding force is lower. In addition, even a slight gap between the magnet’s surface and the plate lowers the load capacity.

Precautions when working with neodymium magnets

Magnet fragility

NdFeB magnets are ceramic materials, which means they are fragile like glass. Impact of two magnets leads to them breaking into shards.

Choking Hazard

Neodymium magnets are not toys. Eating several magnets can lead to them connecting inside the digestive tract, which poses a critical condition and necessitates immediate surgery.

Fire warning

Dust generated during grinding of magnets is flammable. Do not drill into magnets unless you are an expert.

Electronic hazard

Device Safety: Neodymium magnets can damage data carriers and sensitive devices (pacemakers, medical aids, mechanical watches).

Pinching danger

Protect your hands. Two large magnets will join immediately with a force of massive weight, destroying everything in their path. Exercise extreme caution!

Medical interference

Life threat: Strong magnets can turn off heart devices and defibrillators. Do not approach if you have medical devices.

Compass and GPS

Navigation devices and smartphones are highly sensitive to magnetism. Close proximity with a powerful NdFeB magnet can decalibrate the internal compass in your phone.

Sensitization to coating

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

Handling rules

Before starting, read the rules. Sudden snapping can break the magnet or injure your hand. Be predictive.

Heat sensitivity

Regular neodymium magnets (grade N) lose power when the temperature goes above 80°C. The loss of strength is permanent.

Security! Looking for details? Read our article: 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 simulation of the magnet - data

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

Table 2: Shear load (vertical surface) MP 25x13x4 / N38

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

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

Table 5: Working in heat (material behavior) - power drop MP 25x13x4 / N38

Table 6: Magnet-Magnet interaction (repulsion) - field range MP 25x13x4 / N38

Table 7: Protective zones (implants) - warnings MP 25x13x4 / N38

Table 8: Dynamics (cracking risk) - collision effects MP 25x13x4 / N38

Table 9: Corrosion resistance MP 25x13x4 / N38

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

Table 11: Physics of underwater searching MP 25x13x4 / N38

1. Sliding resistance

2. Steel saturation

3. Power loss vs temp

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

Elemental analysis

Sustainability

Force (pull)

Magnetic Induction

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Pros as well as cons of neodymium magnets.

Strengths

Weaknesses

Pull force analysis

Maximum lifting force for a neodymium magnet – what contributes to it?

Determinants of practical lifting force of a magnet

Precautions when working with neodymium magnets

Magnet fragility

Choking Hazard

Fire warning

Electronic hazard

Pinching danger

Medical interference

Compass and GPS

Sensitization to coating

Handling rules

Heat sensitivity

Physical properties of sintered neodymium magnets Nd₂Fe₁₄B at 20°C

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

Table 2: Shear load (vertical surface)
MP 25x13x4 / N38

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

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

Table 5: Working in heat (material behavior) - power drop
MP 25x13x4 / N38

Table 6: Magnet-Magnet interaction (repulsion) - field range
MP 25x13x4 / N38

Table 7: Protective zones (implants) - warnings
MP 25x13x4 / N38

Table 8: Dynamics (cracking risk) - collision effects
MP 25x13x4 / N38

Table 9: Corrosion resistance
MP 25x13x4 / N38

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

Table 11: Physics of underwater searching
MP 25x13x4 / N38