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MP 20x8/4x5 / 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 030333

GTIN/EAN: 5906301812272

5.00

Diameter

20 mm [±0,1 mm]

internal diameter Ø

8/4 mm [±0,1 mm]

Height

5 mm [±0,1 mm]

Weight

11.31 g

Magnetization Direction

↑ axial

Load capacity

6.65 kg / 65.21 N

Magnetic Induction

277.16 mT / 2772 Gs

Coating

[NiCuNi] Nickel

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Technical data of the product - MP 20x8/4x5 / N38 - ring magnet

Specification / characteristics - MP 20x8/4x5 / N38 - ring magnet

properties

properties	values
Cat. no.	030333
GTIN/EAN	5906301812272
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	5 mm [±0,1 mm]
Weight	11.31 g
Magnetization Direction	↑ axial
Load capacity ~ ?	6.65 kg / 65.21 N
Magnetic Induction ~ ?	277.16 mT / 2772 Gs
Coating	[NiCuNi] Nickel
Manufacturing Tolerance	±0.1 mm

Magnetic properties of material N38

Specification / characteristics MP 20x8/4x5 / 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 product - report

Presented data represent the outcome of a engineering simulation. Results were calculated on algorithms for the material Nd₂Fe₁₄B. Actual conditions may deviate from the simulation results. Treat these calculations as a supplementary guide during assembly planning.

Table 1: Static force (force vs gap) - characteristics
MP 20x8/4x5 / N38

Distance (mm)	Induction (Gauss) / mT	Pull Force (kg/lbs/g/N)	Risk Status
0 mm	2424 Gs 242.4 mT	6.65 kg / 14.66 pounds 6650.0 g / 65.2 N	warning
1 mm	2265 Gs 226.5 mT	5.81 kg / 12.80 pounds 5807.9 g / 57.0 N	warning
2 mm	2070 Gs 207.0 mT	4.85 kg / 10.69 pounds 4851.0 g / 47.6 N	warning
3 mm	1858 Gs 185.8 mT	3.91 kg / 8.61 pounds 3906.5 g / 38.3 N	warning
5 mm	1437 Gs 143.7 mT	2.34 kg / 5.16 pounds 2338.7 g / 22.9 N	warning
10 mm	691 Gs 69.1 mT	0.54 kg / 1.19 pounds 540.5 g / 5.3 N	low risk
15 mm	343 Gs 34.3 mT	0.13 kg / 0.29 pounds 133.3 g / 1.3 N	low risk
20 mm	186 Gs 18.6 mT	0.04 kg / 0.09 pounds 39.3 g / 0.4 N	low risk
30 mm	70 Gs 7.0 mT	0.01 kg / 0.01 pounds 5.5 g / 0.1 N	low risk
50 mm	18 Gs 1.8 mT	0.00 kg / 0.00 pounds 0.4 g / 0.0 N	low risk

Magnetic force weakens sharply per each millimeter of distance. Remember that even a very thin break (e.g., contamination, paint, dust) strongly reduces the pull force. Magnets operate most effectively at the point of direct contact; air break weakens the force. Observe how rapidly the parameters fall, when the product does not adhere directly to the metal substrate. When calculating the assembly, discard additional spacers.

Table 2: Shear hold (wall)
MP 20x8/4x5 / N38

Distance (mm)	Friction coefficient	Pull Force (kg/lbs/g/N)
0 mm	Stal (~0.2)	1.33 kg / 2.93 pounds 1330.0 g / 13.0 N
1 mm	Stal (~0.2)	1.16 kg / 2.56 pounds 1162.0 g / 11.4 N
2 mm	Stal (~0.2)	0.97 kg / 2.14 pounds 970.0 g / 9.5 N
3 mm	Stal (~0.2)	0.78 kg / 1.72 pounds 782.0 g / 7.7 N
5 mm	Stal (~0.2)	0.47 kg / 1.03 pounds 468.0 g / 4.6 N
10 mm	Stal (~0.2)	0.11 kg / 0.24 pounds 108.0 g / 1.1 N
15 mm	Stal (~0.2)	0.03 kg / 0.06 pounds 26.0 g / 0.3 N
20 mm	Stal (~0.2)	0.01 kg / 0.02 pounds 8.0 g / 0.1 N
30 mm	Stal (~0.2)	0.00 kg / 0.00 pounds 2.0 g / 0.0 N
50 mm	Stal (~0.2)	0.00 kg / 0.00 pounds 0.0 g / 0.0 N

This section defines the estimated shear load needed to initiate the sliding of the magnet down on a vertical metal surface (considering standard friction). The holding force is relative to the separation distance between the magnet and the surface.

Table 3: Wall mounting (shearing) - vertical pull
MP 20x8/4x5 / N38

Surface type	Friction coefficient / % Mocy	Max load (kg/lbs/g/N)
Raw steel	µ = 0.3 30% Nominalnej Siły	2.00 kg / 4.40 pounds 1995.0 g / 19.6 N
Painted steel (standard)	µ = 0.2 20% Nominalnej Siły	1.33 kg / 2.93 pounds 1330.0 g / 13.0 N
Oily/slippery steel	µ = 0.1 10% Nominalnej Siły	0.67 kg / 1.47 pounds 665.0 g / 6.5 N
Magnet with anti-slip rubber	µ = 0.5 50% Nominalnej Siły	3.33 kg / 7.33 pounds 3325.0 g / 32.6 N

When hanging a holder on a upright wall (e.g., a car body), it will maintain just about 1/5 of its maximum pull force. Gravitational force and a weak degree of grip influence the fact that products slide down easier than they pull off. Designing a hanger? Consider that the shear force is significantly lower than the perpendicular breakaway force. On a smooth steel, the magnet will give way down under a significantly smaller cargo. Application of an anti-slip coating can significantly improve the result.

Table 4: Material efficiency (substrate influence) - sheet metal selection
MP 20x8/4x5 / N38

Steel thickness (mm)	% power	Real pull force (kg/lbs/g/N)
0.5 mm	10%	0.67 kg / 1.47 pounds 665.0 g / 6.5 N
1 mm	25%	1.66 kg / 3.67 pounds 1662.5 g / 16.3 N
2 mm	50%	3.33 kg / 7.33 pounds 3325.0 g / 32.6 N
3 mm	75%	4.99 kg / 11.00 pounds 4987.5 g / 48.9 N
5 mm	100%	6.65 kg / 14.66 pounds 6650.0 g / 65.2 N
10 mm	100%	6.65 kg / 14.66 pounds 6650.0 g / 65.2 N
11 mm	100%	6.65 kg / 14.66 pounds 6650.0 g / 65.2 N
12 mm	100%	6.65 kg / 14.66 pounds 6650.0 g / 65.2 N

A thin metal plate is incapable of absorb the entire magnetic field, which squanders power of the magnet. If you attach a powerful product to a weak sheet, the magnetism will pass right through and the attraction force will be weaker. To achieve full efficiency of this neodymium's potential, you require a sufficiently solid element of steel. The material oversaturation causes that on thin elements (e.g., thin profiles), the holder shows lower pull force. We recommend selecting the steel dimension according to the table below.

Table 5: Thermal resistance (stability) - power drop
MP 20x8/4x5 / N38

Ambient temp. (°C)	Power loss	Remaining pull (kg/lbs/g/N)	Status
20 °C	0.0%	6.65 kg / 14.66 pounds 6650.0 g / 65.2 N	OK
40 °C	-2.2%	6.50 kg / 14.34 pounds 6503.7 g / 63.8 N	OK
60 °C	-4.4%	6.36 kg / 14.02 pounds 6357.4 g / 62.4 N
80 °C	-6.6%	6.21 kg / 13.69 pounds 6211.1 g / 60.9 N
100 °C	-28.8%	4.73 kg / 10.44 pounds 4734.8 g / 46.4 N

Standard neodymium magnets change their properties strength above the temperature limit. Watch out for overheating – high temperature can irreversibly demagnetize this magnet. With increasing heat, the magnet's force temporarily decreases. Refrain from using this magnet near heat sources higher than its working range. Too high temperature will lead to irreversible degradation of magnetism.

*Engineering note: Thermal stability depends not only on the material grade, and the Permeance Coefficient Pc. Thin magnets (low permeance coefficient) may lose charge permanently under lower heat stress compared to rod magnets. The danger warning in the table points to permanent field degradation for this particular item.

Table 6: Magnet-Magnet interaction (repulsion) - forces in the system
MP 20x8/4x5 / N38

Gap (mm)	Attraction (kg/lbs) (N-S)	Sliding Force (kg/lbs/g/N)	Repulsion (kg/lbs) (N-N)
0 mm	9.28 kg / 20.47 pounds 4 012 Gs	1.39 kg / 3.07 pounds 1393 g / 13.7 N	N/A
1 mm	8.73 kg / 19.25 pounds 4 701 Gs	1.31 kg / 2.89 pounds 1310 g / 12.8 N	7.86 kg / 17.33 pounds ~0 Gs
2 mm	8.11 kg / 17.88 pounds 4 530 Gs	1.22 kg / 2.68 pounds 1216 g / 11.9 N	7.30 kg / 16.09 pounds ~0 Gs
3 mm	7.45 kg / 16.42 pounds 4 342 Gs	1.12 kg / 2.46 pounds 1117 g / 11.0 N	6.70 kg / 14.78 pounds ~0 Gs
5 mm	6.10 kg / 13.45 pounds 3 930 Gs	0.92 kg / 2.02 pounds 915 g / 9.0 N	5.49 kg / 12.11 pounds ~0 Gs
10 mm	3.27 kg / 7.20 pounds 2 875 Gs	0.49 kg / 1.08 pounds 490 g / 4.8 N	2.94 kg / 6.48 pounds ~0 Gs
20 mm	0.75 kg / 1.66 pounds 1 382 Gs	0.11 kg / 0.25 pounds 113 g / 1.1 N	0.68 kg / 1.50 pounds ~0 Gs
50 mm	0.02 kg / 0.04 pounds 220 Gs	0.00 kg / 0.01 pounds 3 g / 0.0 N	0.02 kg / 0.04 pounds ~0 Gs
60 mm	0.01 kg / 0.02 pounds 139 Gs	0.00 kg / 0.00 pounds 1 g / 0.0 N	0.00 kg / 0.00 pounds ~0 Gs
70 mm	0.00 kg / 0.01 pounds 93 Gs	0.00 kg / 0.00 pounds 1 g / 0.0 N	0.00 kg / 0.00 pounds ~0 Gs
80 mm	0.00 kg / 0.00 pounds 65 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 47 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 35 Gs	0.00 kg / 0.00 pounds 0 g / 0.0 N	0.00 kg / 0.00 pounds ~0 Gs

Two strong neodymiums attract each other from a significantly greater distance than a neodymium and metal setup. The connection of two magnets creates a more powerful interaction and a further horizon of performance. Planning to create a powerful holder? Use a pair of magnets instead of one magnet and a steel. Exercise caution that when attracting two neodymiums, the pinch force is huge. The levitation is slightly lower than the connection force, but still significant.
*Flux density between like poles drops to ~0 Gs at the midpoint between the magnets (due to field cancellation).
* Results refer to friction force of dual same magnets (friction coefficient ~0.15 for Ni-Ni plating).

Table 7: Hazards (electronics) - warnings
MP 20x8/4x5 / N38

Object / Device	Limit (Gauss) / mT	Safe distance
Pacemaker	5 Gs (0.5 mT)	8.0 cm
Hearing aid	10 Gs (1.0 mT)	6.5 cm
Timepiece	20 Gs (2.0 mT)	5.0 cm
Mobile device	40 Gs (4.0 mT)	4.0 cm
Car key	50 Gs (5.0 mT)	3.5 cm
Payment card	400 Gs (40.0 mT)	1.5 cm
HDD hard drive	600 Gs (60.0 mT)	1.5 cm

Powerful magnet radiation poses a real danger to IT equipment and pacemakers. These neodymiums produce a field that prevents correct functioning of digital equipment. Remember: the unseen radiation penetrates the body and glass. Increased vigilance must be exercised by people with cochlear implants and drug dispensers. The risk also applies to: mechanical watches, remotes, speakers, and screens. Avoid contact with magnetic cards, hard drives, or sensitive navigation tools.

Table 8: Collisions (cracking risk) - collision effects
MP 20x8/4x5 / N38

Start from (mm)	Speed (km/h)	Energy (J)
10 mm	25.67 km/h (7.13 m/s)	0.29 J
30 mm	42.38 km/h (11.77 m/s)	0.78 J
50 mm	54.68 km/h (15.19 m/s)	1.30 J
100 mm	77.33 km/h (21.48 m/s)	2.61 J

NdFeB products are prone to chipping – a collision with steel can result in shattering. Watch the impact speed – a magnet released freely speeds with massive force. Impact energy can cause material chips or painful pinches to skin. Hold the magnet firmly during installation 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. Wear safety glasses when working with powerful specimens.

Table 9: Coating parameters (durability)
MP 20x8/4x5 / 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)

Neodymium magnets are highly susceptible to corrosion without proper protection. Moisture resistance is crucial for installations in bathrooms or outdoors.

Table 10: Electrical data (Flux)
MP 20x8/4x5 / N38

Parameter	Value	SI Unit / Description
Magnetic Flux	7 218 Mx	72.2 µWb
P_c Coefficient	0.31	Low (Flat)

Flux value passing through the pole surface. Key data for generator designers as well as sensors. P_c value determines the working geometry.

Table 11: Submerged application
MP 20x8/4x5 / N38

Environment	Effective steel pull	Effect
Air (land)	6.65 kg	Standard
Water (riverbed)	7.61 kg (+0.96 kg buoyancy gain)	+14.5%

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

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

1. Sliding resistance

*Caution: On a vertical wall, the magnet holds only a fraction of its max power.

2. Efficiency vs thickness

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

3. Thermal stability

*For standard magnets, 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) = 0.31

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.

Technical specification and ecology

Elemental analysis

iron (Fe)	64% – 68%
neodymium (Nd)	29% – 32%
boron (B)	1.1% – 1.2%
dysprosium (Dy)	0.5% – 2.0%
coating (Ni-Cu-Ni)	< 0.05%

Environmental data

recyclability (EoL)	100%
recycled raw materials	~10% (pre-cons)
carbon footprint	low / zredukowany
waste code (EWC)	16 02 16

Safety card (GPSR)

responsible entity

Dhit sp. z o.o.

ul. Kościuszki 6A, 05-850 Ożarów Mazowiecki

tel: +48 22 499 98 98 | e-mail: bok@dhit.pl

batch number/type

id: 030333-2026

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The ring-shaped magnet MP 20x8/4x5 / N38 is created for mechanical fastening, where glue might fail or be insufficient. Mounting is clean and reversible, unlike gluing. This product with a force of 6.65 kg works great as a door latch, speaker holder, or mounting element in devices.

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.

These magnets are coated with standard Ni-Cu-Ni plating, which protects them in indoor conditions, but is not sufficient for rain. Damage to the protective layer during assembly is the most common cause of rusting. If you must use it outside, paint it with anti-corrosion paint after mounting.

A screw or bolt with a thread diameter smaller than 8/4 mm fits this model. 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.

This model is characterized by dimensions Ø20x5 mm and a weight of 11.31 g. The key parameter here is the lifting capacity amounting to approximately 6.65 kg (force ~65.21 N). The product has a [NiCuNi] coating and is made of NdFeB material. Inner hole dimension: 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. We do not offer paired sets with marked poles in this category, but they are easy to match manually.

Pros and cons of neodymium magnets.

Pros

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

They retain attractive force for almost ten years – the drop is just ~1% (in theory),
Magnets perfectly defend themselves against demagnetization caused by external fields,
Thanks to the shiny finish, the plating of nickel, gold-plated, or silver-plated gives an professional appearance,
Magnetic induction on the working layer of the magnet turns out to be maximum,
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 modularity in designing and the ability to modify to individual projects,
Wide application in high-tech industry – they are utilized in hard drives, motor assemblies, advanced medical instruments, as well as modern systems.
Compactness – despite small sizes they provide effective action, making them ideal for precision applications

Limitations

Disadvantages of neodymium magnets:

To avoid cracks under impact, we recommend using special steel holders. Such a solution protects the magnet and simultaneously improves its durability.
Neodymium magnets demagnetize when exposed to high temperatures. After reaching 80°C, many of them experience permanent drop of strength (a factor is the shape as well as dimensions of the magnet). We offer magnets specially adapted to work at temperatures up to 230°C marked [AH], which are extremely resistant to heat
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.
We suggest a housing - magnetic mechanism, due to difficulties in creating nuts inside the magnet and complicated forms.
Health risk resulting from small fragments of magnets pose a threat, in case of ingestion, which is particularly important in the aspect of protecting the youngest. Furthermore, small elements of these magnets can be problematic in diagnostics medical in case of swallowing.
Due to complex production process, their price is relatively high,

Lifting parameters

Breakaway strength of the magnet in ideal conditions – what contributes to it?

Magnet power was determined for optimal configuration, assuming:

on a plate made of mild steel, optimally conducting the magnetic flux
possessing a thickness of minimum 10 mm to ensure full flux closure
with an ground contact surface
without the slightest clearance between the magnet and steel
under axial application of breakaway force (90-degree angle)
at ambient temperature room level

Determinants of practical lifting force of a magnet

In practice, the actual lifting capacity depends on several key aspects, presented from the most important:

Gap between surfaces – every millimeter of separation (caused e.g. by varnish or dirt) drastically reduces the pulling force, often by half at just 0.5 mm.
Force direction – note that the magnet holds strongest perpendicularly. Under shear forces, the capacity drops drastically, often to levels of 20-30% of the maximum value.
Plate thickness – insufficiently thick sheet causes magnetic saturation, causing part of the flux to be lost into the air.
Steel type – mild steel gives the best results. Alloy admixtures lower magnetic properties and lifting capacity.
Surface structure – the more even the surface, the better the adhesion and stronger the hold. Unevenness acts like micro-gaps.
Thermal factor – high temperature reduces magnetic field. Exceeding the limit temperature can permanently damage the magnet.

Lifting capacity was determined by applying a steel plate with a smooth surface of suitable thickness (min. 20 mm), under vertically applied force, whereas under shearing force the load capacity is reduced by as much as 75%. Moreover, even a minimal clearance between the magnet’s surface and the plate lowers the load capacity.

H&S for magnets

Pinching danger

Risk of injury: The attraction force is so great that it can cause blood blisters, pinching, and even bone fractures. Protective gloves are recommended.

Do not give to children

Neodymium magnets are not intended for children. Accidental ingestion of a few magnets may result in them attracting across intestines, which poses a critical condition and necessitates urgent medical intervention.

Compass and GPS

A strong magnetic field interferes with the operation of compasses in phones and GPS navigation. Do not bring magnets close to a smartphone to avoid breaking the sensors.

Electronic devices

Data protection: Strong magnets can damage payment cards and sensitive devices (heart implants, medical aids, mechanical watches).

Protective goggles

Watch out for shards. Magnets can explode upon uncontrolled impact, ejecting sharp fragments into the air. Wear goggles.

Safe operation

Before starting, check safety instructions. Uncontrolled attraction can destroy the magnet or hurt your hand. Think ahead.

Implant safety

Patients with a ICD should keep an absolute distance from magnets. The magnetic field can stop the operation of the life-saving device.

Dust explosion hazard

Powder produced during machining of magnets is combustible. Do not drill into magnets without proper cooling and knowledge.

Demagnetization risk

Do not overheat. Neodymium magnets are susceptible to temperature. If you need resistance above 80°C, ask us about HT versions (H, SH, UH).

Metal Allergy

Allergy Notice: The nickel-copper-nickel coating consists of nickel. If an allergic reaction happens, cease working with magnets and use protective gear.

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

MP 20x8/4x5 / N38 - ring magnet

Technical data of the product - MP 20x8/4x5 / N38 - ring magnet

Magnetic properties of material N38

Physical properties of sintered neodymium magnets Nd2Fe14B at 20°C

Technical simulation of the product - report

Table 1: Static force (force vs gap) - characteristics MP 20x8/4x5 / N38

Table 2: Shear hold (wall) MP 20x8/4x5 / N38

Table 3: Wall mounting (shearing) - vertical pull MP 20x8/4x5 / N38

Table 4: Material efficiency (substrate influence) - sheet metal selection MP 20x8/4x5 / N38

Table 5: Thermal resistance (stability) - power drop MP 20x8/4x5 / N38

Table 6: Magnet-Magnet interaction (repulsion) - forces in the system MP 20x8/4x5 / N38

Table 7: Hazards (electronics) - warnings MP 20x8/4x5 / N38

Table 8: Collisions (cracking risk) - collision effects MP 20x8/4x5 / N38

Table 9: Coating parameters (durability) MP 20x8/4x5 / N38

Table 10: Electrical data (Flux) MP 20x8/4x5 / N38

Table 11: Submerged application MP 20x8/4x5 / N38

1. Sliding resistance

2. Efficiency vs thickness

3. Thermal stability

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

Elemental analysis

Environmental data

Pulling force

Magnetic Field

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Pros and cons of neodymium magnets.

Pros

Limitations

Lifting parameters

Breakaway strength of the magnet in ideal conditions – what contributes to it?

Determinants of practical lifting force of a magnet

H&S for magnets

Pinching danger

Do not give to children

Compass and GPS

Electronic devices

Protective goggles

Safe operation

Implant safety

Dust explosion hazard

Demagnetization risk

Metal Allergy

Physical properties of sintered neodymium magnets Nd₂Fe₁₄B at 20°C

Table 1: Static force (force vs gap) - characteristics
MP 20x8/4x5 / N38

Table 2: Shear hold (wall)
MP 20x8/4x5 / N38

Table 3: Wall mounting (shearing) - vertical pull
MP 20x8/4x5 / N38

Table 4: Material efficiency (substrate influence) - sheet metal selection
MP 20x8/4x5 / N38

Table 5: Thermal resistance (stability) - power drop
MP 20x8/4x5 / N38

Table 6: Magnet-Magnet interaction (repulsion) - forces in the system
MP 20x8/4x5 / N38

Table 7: Hazards (electronics) - warnings
MP 20x8/4x5 / N38

Table 8: Collisions (cracking risk) - collision effects
MP 20x8/4x5 / N38

Table 9: Coating parameters (durability)
MP 20x8/4x5 / N38

Table 10: Electrical data (Flux)
MP 20x8/4x5 / N38

Table 11: Submerged application
MP 20x8/4x5 / N38