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MP 20x8/4x3 / 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 030187

GTIN/EAN: 5906301812043

5.00

Diameter

20 mm [±0,1 mm]

internal diameter Ø

8/4 mm [±0,1 mm]

Height

3 mm [±0,1 mm]

Weight

6.79 g

Magnetization Direction

↑ axial

Load capacity

3.14 kg / 30.79 N

Magnetic Induction

178.11 mT / 1781 Gs

Coating

[NiCuNi] Nickel

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Technical - MP 20x8/4x3 / N38 - ring magnet

Specification / characteristics - MP 20x8/4x3 / N38 - ring magnet

properties

properties	values
Cat. no.	030187
GTIN/EAN	5906301812043
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	20 mm [±0,1 mm]
internal diameter Ø	8/4 mm [±0,1 mm]
Height	3 mm [±0,1 mm]
Weight	6.79 g
Magnetization Direction	↑ axial
Load capacity ~ ?	3.14 kg / 30.79 N
Magnetic Induction ~ ?	178.11 mT / 1781 Gs
Coating	[NiCuNi] Nickel
Manufacturing Tolerance	±0.1 mm

Magnetic properties of material N38

Specification / characteristics MP 20x8/4x3 / 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 - report

These values are the outcome of a engineering calculation. Results were calculated on algorithms for the material Nd₂Fe₁₄B. Operational parameters might slightly differ. Please consider these calculations as a preliminary roadmap when designing systems.

Table 1: Static pull force (pull vs gap) - characteristics
MP 20x8/4x3 / N38

Distance (mm)	Induction (Gauss) / mT	Pull Force (kg/lbs/g/N)	Risk Status
0 mm	1531 Gs 153.1 mT	3.14 kg / 6.92 pounds 3140.0 g / 30.8 N	medium risk
1 mm	1457 Gs 145.7 mT	2.84 kg / 6.27 pounds 2843.2 g / 27.9 N	medium risk
2 mm	1352 Gs 135.2 mT	2.45 kg / 5.39 pounds 2446.6 g / 24.0 N	medium risk
3 mm	1227 Gs 122.7 mT	2.02 kg / 4.44 pounds 2016.2 g / 19.8 N	medium risk
5 mm	963 Gs 96.3 mT	1.24 kg / 2.74 pounds 1241.9 g / 12.2 N	safe
10 mm	465 Gs 46.5 mT	0.29 kg / 0.64 pounds 289.3 g / 2.8 N	safe
15 mm	228 Gs 22.8 mT	0.07 kg / 0.15 pounds 69.7 g / 0.7 N	safe
20 mm	122 Gs 12.2 mT	0.02 kg / 0.04 pounds 20.0 g / 0.2 N	safe
30 mm	45 Gs 4.5 mT	0.00 kg / 0.01 pounds 2.7 g / 0.0 N	safe
50 mm	11 Gs 1.1 mT	0.00 kg / 0.00 pounds 0.2 g / 0.0 N	safe

Grip strength weakens significantly per each millimeter of gap. Remember that every additional insulation layer (e.g., dirt, paint, veneer) noticeably reduces the pull force. Magnetic products operate optimally at the point of direct contact; gap nullifies the power. Notice how quickly the load capacity plummet, when the magnet does not adhere flatly to the metal substrate. When planning the mounting, discard redundant distances.

Table 2: Slippage load (vertical surface)
MP 20x8/4x3 / N38

Distance (mm)	Friction coefficient	Pull Force (kg/lbs/g/N)
0 mm	Stal (~0.2)	0.63 kg / 1.38 pounds 628.0 g / 6.2 N
1 mm	Stal (~0.2)	0.57 kg / 1.25 pounds 568.0 g / 5.6 N
2 mm	Stal (~0.2)	0.49 kg / 1.08 pounds 490.0 g / 4.8 N
3 mm	Stal (~0.2)	0.40 kg / 0.89 pounds 404.0 g / 4.0 N
5 mm	Stal (~0.2)	0.25 kg / 0.55 pounds 248.0 g / 2.4 N
10 mm	Stal (~0.2)	0.06 kg / 0.13 pounds 58.0 g / 0.6 N
15 mm	Stal (~0.2)	0.01 kg / 0.03 pounds 14.0 g / 0.1 N
20 mm	Stal (~0.2)	0.00 kg / 0.01 pounds 4.0 g / 0.0 N
30 mm	Stal (~0.2)	0.00 kg / 0.00 pounds 0.0 g / 0.0 N
50 mm	Stal (~0.2)	0.00 kg / 0.00 pounds 0.0 g / 0.0 N

The table below indicates the estimated shear load necessary to initiate the slippage of the magnet vertically on a vertical steel plate (considering standard friction coefficient). This value varies with the separation distance between the magnet and the metal.

Table 3: Wall mounting (sliding) - vertical pull
MP 20x8/4x3 / N38

Surface type	Friction coefficient / % Mocy	Max load (kg/lbs/g/N)
Raw steel	µ = 0.3 30% Nominalnej Siły	0.94 kg / 2.08 pounds 942.0 g / 9.2 N
Painted steel (standard)	µ = 0.2 20% Nominalnej Siły	0.63 kg / 1.38 pounds 628.0 g / 6.2 N
Oily/slippery steel	µ = 0.1 10% Nominalnej Siły	0.31 kg / 0.69 pounds 314.0 g / 3.1 N
Magnet with anti-slip rubber	µ = 0.5 50% Nominalnej Siły	1.57 kg / 3.46 pounds 1570.0 g / 15.4 N

When mounting a holder on a upright surface (e.g., a car body), it will only hold just approx. 20%-30% of nominal attraction strength. Gravity as well as a low friction coefficient influence the fact that holders slide down faster than they detach. Designing a wall mount? Consider that the shear force is much weaker than the maximum static pull force. On a slippery surface, the holder will slide down under a much lighter load. Application of an anti-slip coating can drastically improve the result.

Table 4: Material efficiency (substrate influence) - power losses
MP 20x8/4x3 / N38

Steel thickness (mm)	% power	Real pull force (kg/lbs/g/N)
0.5 mm	10%	0.31 kg / 0.69 pounds 314.0 g / 3.1 N
1 mm	25%	0.79 kg / 1.73 pounds 785.0 g / 7.7 N
2 mm	50%	1.57 kg / 3.46 pounds 1570.0 g / 15.4 N
3 mm	75%	2.36 kg / 5.19 pounds 2355.0 g / 23.1 N
5 mm	100%	3.14 kg / 6.92 pounds 3140.0 g / 30.8 N
10 mm	100%	3.14 kg / 6.92 pounds 3140.0 g / 30.8 N
11 mm	100%	3.14 kg / 6.92 pounds 3140.0 g / 30.8 N
12 mm	100%	3.14 kg / 6.92 pounds 3140.0 g / 30.8 N

A thin sheet is not enough to conduct the entire magnetic field, which squanders power of the holder. Should you attach a powerful product to a too thin substrate, the magnetism will pass right through and the attraction force will be weaker. To squeeze full efficiency of this neodymium's power, you need a suitably thick piece of steel. The material oversaturation causes that on delicate walls (e.g., thin profiles), the holder holds weaker. We recommend selecting the steel thickness according to the table below.

Table 5: Thermal resistance (material behavior) - power drop
MP 20x8/4x3 / N38

Ambient temp. (°C)	Power loss	Remaining pull (kg/lbs/g/N)	Status
20 °C	0.0%	3.14 kg / 6.92 pounds 3140.0 g / 30.8 N	OK
40 °C	-2.2%	3.07 kg / 6.77 pounds 3070.9 g / 30.1 N	OK
60 °C	-4.4%	3.00 kg / 6.62 pounds 3001.8 g / 29.4 N
80 °C	-6.6%	2.93 kg / 6.47 pounds 2932.8 g / 28.8 N
100 °C	-28.8%	2.24 kg / 4.93 pounds 2235.7 g / 21.9 N

Ordinary NdFeB products change their properties strength above the temperature limit. Watch out for overheating – excessive heat can irreversibly demagnetize this magnet. With increasing heat, the neodymium's force temporarily lowers. Avoid using this magnet near heat sources higher than its working range. Ignoring the limit will lead to destruction of magnetic properties.

*Technical advisory: Heat tolerance is determined by both grade, and the Permeance Coefficient Pc. Low-profile magnets (low permeance coefficient) may lose charge permanently sooner compared to rod magnets. Red status in the table signals a risk of irreversible loss for this particular item.

Table 6: Magnet-Magnet interaction (repulsion) - field range
MP 20x8/4x3 / N38

Gap (mm)	Attraction (kg/lbs) (N-S)	Sliding Force (kg/lbs/g/N)	Repulsion (kg/lbs) (N-N)
0 mm	3.71 kg / 8.17 pounds 2 815 Gs	0.56 kg / 1.23 pounds 556 g / 5.5 N	N/A
1 mm	3.55 kg / 7.83 pounds 2 998 Gs	0.53 kg / 1.17 pounds 533 g / 5.2 N	3.20 kg / 7.05 pounds ~0 Gs
2 mm	3.36 kg / 7.40 pounds 2 915 Gs	0.50 kg / 1.11 pounds 503 g / 4.9 N	3.02 kg / 6.66 pounds ~0 Gs
3 mm	3.13 kg / 6.90 pounds 2 815 Gs	0.47 kg / 1.04 pounds 470 g / 4.6 N	2.82 kg / 6.21 pounds ~0 Gs
5 mm	2.63 kg / 5.81 pounds 2 582 Gs	0.40 kg / 0.87 pounds 395 g / 3.9 N	2.37 kg / 5.23 pounds ~0 Gs
10 mm	1.47 kg / 3.23 pounds 1 926 Gs	0.22 kg / 0.48 pounds 220 g / 2.2 N	1.32 kg / 2.91 pounds ~0 Gs
20 mm	0.34 kg / 0.75 pounds 930 Gs	0.05 kg / 0.11 pounds 51 g / 0.5 N	0.31 kg / 0.68 pounds ~0 Gs
50 mm	0.01 kg / 0.02 pounds 143 Gs	0.00 kg / 0.00 pounds 1 g / 0.0 N	0.00 kg / 0.00 pounds ~0 Gs
60 mm	0.00 kg / 0.01 pounds 90 Gs	0.00 kg / 0.00 pounds 0 g / 0.0 N	0.00 kg / 0.00 pounds ~0 Gs
70 mm	0.00 kg / 0.00 pounds 59 Gs	0.00 kg / 0.00 pounds 0 g / 0.0 N	0.00 kg / 0.00 pounds ~0 Gs
80 mm	0.00 kg / 0.00 pounds 41 Gs	0.00 kg / 0.00 pounds 0 g / 0.0 N	0.00 kg / 0.00 pounds ~0 Gs
90 mm	0.00 kg / 0.00 pounds 30 Gs	0.00 kg / 0.00 pounds 0 g / 0.0 N	0.00 kg / 0.00 pounds ~0 Gs
100 mm	0.00 kg / 0.00 pounds 22 Gs	0.00 kg / 0.00 pounds 0 g / 0.0 N	0.00 kg / 0.00 pounds ~0 Gs

Two magnets attract each other from a significantly greater distance than a magnet and steel setup. The setup of two magnets creates a more powerful interaction and a larger range of operation. Want to build a strong closure? Use a pair of magnets instead of one magnet and a striker plate. Be careful that when attracting two neodymiums, the impact force is massive. The levitation is a bit weaker than the attraction, but still impressive.
*Field value between like poles reaches ~0 Gs in the exact middle between the magnets (due to field cancellation).
Important: Results apply to friction force of a pair of matching magnets (friction coefficient ~0.15 for Ni-Ni layer).

Table 7: Hazards (implants) - precautionary measures
MP 20x8/4x3 / N38

Object / Device	Limit (Gauss) / mT	Safe distance
Pacemaker	5 Gs (0.5 mT)	7.0 cm
Hearing aid	10 Gs (1.0 mT)	5.5 cm
Mechanical watch	20 Gs (2.0 mT)	4.5 cm
Mobile device	40 Gs (4.0 mT)	3.5 cm
Car key	50 Gs (5.0 mT)	3.0 cm
Payment card	400 Gs (40.0 mT)	1.5 cm
HDD hard drive	600 Gs (60.0 mT)	1.0 cm

Powerful magnet radiation is a large risk to electronic devices as well as pacemakers. These neodymiums generate a flux that disrupts operation of digital equipment. Be aware: the unseen radiation acts through matter and glass. Exceptional care must be exercised by people with hearing aids and drug dispensers. Influence will be felt by: mechanical watches, car keys, speakers, and screens. Do not place the magnet near cards, HDD media, or precise measuring instruments.

Table 8: Dynamics (kinetic energy) - collision effects
MP 20x8/4x3 / N38

Start from (mm)	Speed (km/h)	Energy (J)
10 mm	22.90 km/h (6.36 m/s)	0.14 J
30 mm	37.58 km/h (10.44 m/s)	0.37 J
50 mm	48.50 km/h (13.47 m/s)	0.62 J
100 mm	68.58 km/h (19.05 m/s)	1.23 J

Neodymium magnets are delicate – a collision with steel can result in shattering. Pay attention to connection velocity – a neodymium left loose turns into a projectile. Kinetic force can destroy the magnet or injury to fingers. Always hold the magnet during installation so it doesn't slam with momentum against the metal. A contact at a velocity of dozens of km/h almost guarantees destruction of the magnet. Use safety goggles when playing with large magnets.

Table 9: Corrosion resistance
MP 20x8/4x3 / N38

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

The SST (salt spray test) is an industry standard for determining coating lifespan in harsh conditions. The silver nickel coating also serves an aesthetic function but is not fully waterproof.

Table 10: Electrical data (P_c)
MP 20x8/4x3 / N38

Parameter	Value	SI Unit / Description
Magnetic Flux	5 044 Mx	50.4 µWb
P_c Coefficient	0.20	Low (Flat)

Total magnetic flux passing through the magnet pole. Key data in coil applications and motors. P_c value defines the magnet's operating point.

Table 11: Underwater work (magnet fishing)
MP 20x8/4x3 / N38

Environment	Effective steel pull	Effect
Air (land)	3.14 kg	Standard
Water (riverbed)	3.60 kg (+0.46 kg buoyancy gain)	+14.5%

Corrosion warning: Remember to wipe the magnet thoroughly after removing it from water and apply a protective layer (e.g., oil) to avoid corrosion.

In water, the magnet feels stronger thanks to Archimedes' principle. As a result, your magnet will pull a heavier object from the bottom than if you lifted it in the air.

1. Shear force

*Warning: On a vertical surface, the magnet holds just approx. 20-30% of its max power.

2. Steel saturation

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

3. Thermal stability

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

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

chart generated for the permeance coefficient P_c (Permeance Coefficient) = 0.20

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

Technical and environmental data

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%

Ecology and recycling (GPSR)

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: 030187-2026

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The ring-shaped magnet MP 20x8/4x3 / N38 is created for permanent mounting, where glue might fail or be insufficient. Thanks to the hole (often for a screw), this model enables easy screwing to wood, wall, plastic, or metal. This product with a force of 3.14 kg works great as a cabinet closure, speaker holder, or spacer element in devices.

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. 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. For magnets with a straight hole, a conical head can act like a wedge and burst the magnet. Always check that the screw head is not larger than the outer diameter of the magnet (20 mm), so it doesn't protrude beyond the outline.

This model is characterized by dimensions Ø20x3 mm and a weight of 6.79 g. The key parameter here is the lifting capacity amounting to approximately 3.14 kg (force ~30.79 N). The mounting hole diameter is precisely 8/4 mm.

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

Strengths as well as weaknesses of rare earth magnets.

Pros

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

Their strength remains stable, and after approximately 10 years it drops only by ~1% (theoretically),
Neodymium magnets are characterized by extremely resistant to demagnetization caused by magnetic disturbances,
By covering with a shiny layer of silver, the element gains an aesthetic look,
The surface of neodymium magnets generates a maximum magnetic field – this is one of their assets,
Neodymium magnets are characterized by very high magnetic induction on the magnet surface and can function (depending on the form) even at a temperature of 230°C or more...
Possibility of precise forming as well as adapting to specific applications,
Huge importance in modern industrial fields – they are utilized in hard drives, brushless drives, medical devices, and other advanced devices.
Relatively small size with high pulling force – neodymium magnets offer impressive pulling force in compact dimensions, which makes them useful in miniature devices

Weaknesses

Disadvantages of neodymium magnets:

To avoid cracks under impact, we suggest using special steel holders. Such a solution protects the magnet and simultaneously improves its durability.
Neodymium magnets decrease their force under the influence of heating. As soon as 80°C is exceeded, many of them start losing their power. Therefore, we recommend our special magnets marked [AH], which maintain stability even at temperatures up to 230°C
When exposed to humidity, magnets start to rust. To use them in conditions outside, it is recommended to use protective magnets, such as those in rubber or plastics, which prevent oxidation as well as corrosion.
Limited ability of creating threads in the magnet and complex shapes - preferred is casing - magnet mounting.
Possible danger to health – tiny shards of magnets pose a threat, in case of ingestion, which is particularly important in the aspect of protecting the youngest. It is also worth noting that small components of these products can disrupt the diagnostic process medical in case of swallowing.
Higher cost of purchase is one of the disadvantages compared to ceramic magnets, especially in budget applications

Holding force characteristics

Magnetic strength at its maximum – what it depends on?

The declared magnet strength refers to the maximum value, measured under optimal environment, specifically:

with the application of a yoke made of low-carbon steel, guaranteeing full magnetic saturation
with a cross-section minimum 10 mm
characterized by lack of roughness
under conditions of gap-free contact (metal-to-metal)
for force acting at a right angle (in the magnet axis)
at room temperature

Determinants of lifting force in real conditions

It is worth knowing that the working load will differ influenced by elements below, starting with the most relevant:

Gap (between the magnet and the plate), since even a tiny distance (e.g. 0.5 mm) results in a decrease in lifting capacity by up to 50% (this also applies to paint, rust or debris).
Angle of force application – highest force is reached only during perpendicular pulling. The resistance to sliding of the magnet along the plate is standardly many times smaller (approx. 1/5 of the lifting capacity).
Element thickness – for full efficiency, the steel must be adequately massive. Thin sheet limits the lifting capacity (the magnet "punches through" it).
Steel grade – the best choice is pure iron steel. Hardened steels may generate lower lifting capacity.
Surface condition – smooth surfaces guarantee perfect abutment, which improves field saturation. Uneven metal weaken the grip.
Temperature influence – high temperature weakens magnetic field. Too high temperature can permanently damage the magnet.

Holding force was tested on a smooth steel plate of 20 mm thickness, when the force acted perpendicularly, however under attempts to slide the magnet the lifting capacity is smaller. Additionally, even a minimal clearance between the magnet and the plate decreases the load capacity.

Precautions when working with NdFeB magnets

Crushing risk

Watch your fingers. Two powerful magnets will join instantly with a force of massive weight, crushing everything in their path. Be careful!

Nickel coating and allergies

Warning for allergy sufferers: The Ni-Cu-Ni coating contains nickel. If redness appears, cease working with magnets and wear gloves.

Fire warning

Combustion risk: Rare earth powder is explosive. Avoid machining magnets in home conditions as this risks ignition.

Pacemakers

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

Handling rules

Be careful. Rare earth magnets act from a long distance and snap with huge force, often faster than you can react.

This is not a toy

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

Safe distance

Avoid bringing magnets near a purse, laptop, or TV. The magnetism can irreversibly ruin these devices and wipe information from cards.

Operating temperature

Do not overheat. Neodymium magnets are sensitive to temperature. If you require operation above 80°C, inquire about HT versions (H, SH, UH).

GPS and phone interference

GPS units and mobile phones are extremely susceptible to magnetic fields. Direct contact with a powerful NdFeB magnet can decalibrate the sensors in your phone.

Risk of cracking

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

Caution! Learn more about risks in the article: Safety of working with magnets.

MP 20x8/4x3 / N38 - ring magnet

Technical - MP 20x8/4x3 / N38 - ring magnet

Magnetic properties of material N38

Physical properties of sintered neodymium magnets Nd2Fe14B at 20°C

Technical analysis of the assembly - report

Table 1: Static pull force (pull vs gap) - characteristics MP 20x8/4x3 / N38

Table 2: Slippage load (vertical surface) MP 20x8/4x3 / N38

Table 3: Wall mounting (sliding) - vertical pull MP 20x8/4x3 / N38

Table 4: Material efficiency (substrate influence) - power losses MP 20x8/4x3 / N38

Table 5: Thermal resistance (material behavior) - power drop MP 20x8/4x3 / N38

Table 6: Magnet-Magnet interaction (repulsion) - field range MP 20x8/4x3 / N38

Table 7: Hazards (implants) - precautionary measures MP 20x8/4x3 / N38

Table 8: Dynamics (kinetic energy) - collision effects MP 20x8/4x3 / N38

Table 9: Corrosion resistance MP 20x8/4x3 / N38

Table 10: Electrical data (Pc) MP 20x8/4x3 / N38

Table 11: Underwater work (magnet fishing) MP 20x8/4x3 / N38

1. Shear force

2. Steel saturation

3. Thermal stability

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

Elemental analysis

Ecology and recycling (GPSR)

Force (pull)

Magnetic Field

Other proposals

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MP 8x6/3.5x3 / N38 - ring magnet

MPL 40x7x3 / N38 - lamellar magnet

UMS 16x6.5x3.5x5 / N38 - conical magnetic holder

Strengths as well as weaknesses of rare earth magnets.

Pros

Weaknesses

Holding force characteristics

Magnetic strength at its maximum – what it depends on?

Determinants of lifting force in real conditions

Precautions when working with NdFeB magnets

Crushing risk

Nickel coating and allergies

Fire warning

Pacemakers

Handling rules

This is not a toy

Safe distance

Operating temperature

GPS and phone interference

Risk of cracking

Physical properties of sintered neodymium magnets Nd₂Fe₁₄B at 20°C

Table 1: Static pull force (pull vs gap) - characteristics
MP 20x8/4x3 / N38

Table 2: Slippage load (vertical surface)
MP 20x8/4x3 / N38

Table 3: Wall mounting (sliding) - vertical pull
MP 20x8/4x3 / N38

Table 4: Material efficiency (substrate influence) - power losses
MP 20x8/4x3 / N38

Table 5: Thermal resistance (material behavior) - power drop
MP 20x8/4x3 / N38

Table 6: Magnet-Magnet interaction (repulsion) - field range
MP 20x8/4x3 / N38

Table 7: Hazards (implants) - precautionary measures
MP 20x8/4x3 / N38

Table 8: Dynamics (kinetic energy) - collision effects
MP 20x8/4x3 / N38

Table 9: Corrosion resistance
MP 20x8/4x3 / N38

Table 10: Electrical data (P_c)
MP 20x8/4x3 / N38

Table 11: Underwater work (magnet fishing)
MP 20x8/4x3 / N38