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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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7.75 ZŁ with VAT / pcs + price for transport

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Technical specification 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

Engineering analysis of the product - report

These data are the outcome of a mathematical simulation. Values rely on models for the material Nd₂Fe₁₄B. Actual performance may deviate from the simulation results. Treat these data as a preliminary roadmap during assembly planning.

Table 1: Static force (pull vs gap) - interaction chart
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 lbs 6650.0 g / 65.2 N	medium risk
1 mm	2265 Gs 226.5 mT	5.81 kg / 12.80 lbs 5807.9 g / 57.0 N	medium risk
2 mm	2070 Gs 207.0 mT	4.85 kg / 10.69 lbs 4851.0 g / 47.6 N	medium risk
3 mm	1858 Gs 185.8 mT	3.91 kg / 8.61 lbs 3906.5 g / 38.3 N	medium risk
5 mm	1437 Gs 143.7 mT	2.34 kg / 5.16 lbs 2338.7 g / 22.9 N	medium risk
10 mm	691 Gs 69.1 mT	0.54 kg / 1.19 lbs 540.5 g / 5.3 N	weak grip
15 mm	343 Gs 34.3 mT	0.13 kg / 0.29 lbs 133.3 g / 1.3 N	weak grip
20 mm	186 Gs 18.6 mT	0.04 kg / 0.09 lbs 39.3 g / 0.4 N	weak grip
30 mm	70 Gs 7.0 mT	0.01 kg / 0.01 lbs 5.5 g / 0.1 N	weak grip
50 mm	18 Gs 1.8 mT	0.00 kg / 0.00 lbs 0.4 g / 0.0 N	weak grip

Grip strength drops sharply with every subsequent millimeter of distance. Remember that even a microscopic distance (e.g., dirt, paint, dust) significantly reduces the pull force. Neodymiums operate strongest during direct contact; gap drastically cuts the force. Analyze how quickly the parameters plummet, when the magnet does not touch tightly to the steel surface. When calculating the assembly, avoid additional spacers.

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

The table below indicates the theoretical weight limit required to start the shifting of the magnet downwards on a upright metal surface (assuming typical friction coefficient). This value is a function of the distance between the magnet and the metal.

Table 3: Wall mounting (sliding) - 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 lbs 1995.0 g / 19.6 N
Painted steel (standard)	µ = 0.2 20% Nominalnej Siły	1.33 kg / 2.93 lbs 1330.0 g / 13.0 N
Oily/slippery steel	µ = 0.1 10% Nominalnej Siły	0.67 kg / 1.47 lbs 665.0 g / 6.5 N
Magnet with anti-slip rubber	µ = 0.5 50% Nominalnej Siły	3.33 kg / 7.33 lbs 3325.0 g / 32.6 N

When placing a element on a upright plane (e.g., a car body), it you can count on just about 20%-30% of nominal attraction strength. Gravitational force as well as a low friction coefficient influence the fact that magnets slide down easier than they pop off the substrate. Planning a vertical fastening? Remember that the sliding force is much weaker than the perpendicular breakaway force. On a painted metal, the magnet will slide down under a significantly smaller cargo. Application of an anti-slip pad can significantly raise the stability.

Table 4: Steel thickness (substrate influence) - power losses
MP 20x8/4x5 / N38

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

A too thin steel is not enough to focus the entire magnetic field, which squanders power of the holder. Should you mount a strong magnet to a too thin substrate, the flux will penetrate right through and the attraction force will be weaker. To squeeze 100% of this neodymium's potential, you require a sufficiently solid backing of steel. The saturation phenomenon means that on sheet metal structures (e.g., car bodies), the product works worse. We suggest choosing the steel thickness from these parameters.

Table 5: Thermal resistance (material behavior) - resistance threshold
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 lbs 6650.0 g / 65.2 N	OK
40 °C	-2.2%	6.50 kg / 14.34 lbs 6503.7 g / 63.8 N	OK
60 °C	-4.4%	6.36 kg / 14.02 lbs 6357.4 g / 62.4 N
80 °C	-6.6%	6.21 kg / 13.69 lbs 6211.1 g / 60.9 N
100 °C	-28.8%	4.73 kg / 10.44 lbs 4734.8 g / 46.4 N

Classic neodymiums lose parameters after exceeding the maximum temperature. Protect against heat – excessive heat can permanently destroy this product. With increasing heat, the neodymium's force temporarily decreases. Refrain from using this product in hot environments higher than its operating temperature limit. Too high temperature will cause permanent loss of magnetism.

*Technical advisory: Temperature resistance depends not only on the material grade, as well as the dimension ratios. Thin magnets (pancake types) may lose charge permanently at lower temperatures than taller cylinders. Red status in the table indicates a risk of irreversible loss for this particular item.

Table 6: Two magnets (repulsion) - field collision
MP 20x8/4x5 / N38

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

Two magnets interact from a wider radius than a neodymium and metal combination. The connection of two magnets produces a massive flux and a larger range of operation. Want to build a powerful holder? Utilize two neodymiums instead of a neodymium and a striker plate. Be careful that when attracting two neodymiums, the impact force is extreme. The repulsion force is marginally weaker than the attraction, but still impressive.
*The magnetic induction in repulsion mode reaches ~0 Gs in the exact middle between the magnets (due to field cancellation).
Note: Estimates demonstrate friction force of a pair of identical neodymium magnets (friction coefficient ~0.15 for Ni-Ni coating).

Table 7: Protective zones (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
Mechanical watch	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

A strong magnetic field poses a serious hazard to IT equipment and pacemakers. These NdFeB products produce a flux that disrupts operation of digital equipment. Remember: the unseen radiation penetrates the body and housings. Special caution must be taken by people with hearing aids and insulin pumps. Influence will be felt by: mechanical watches, car keys, speakers, and displays. Avoid contact with magnetic cards, hard drives, or precise measuring instruments.

Table 8: Collisions (kinetic energy) - 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 delicate – a violent impact against metal causes immediate chipping. Watch the impact speed – a magnet released freely speeds with massive force. Striking energy can destroy the magnet or dangerous crushing to skin. Be sure to control the product during bringing near metal so it doesn't hit violently against the steel surface. A collision at high speed almost guarantees destruction of the neodymium. Wear safety glasses when handling with powerful specimens.

Table 9: Surface protection spec
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)

For outdoor applications, an epoxy coating is required; standard nickel is intended for indoor use. Note the thickness of the protective layer.

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)

Total magnetic flux passing through the pole surface. Essential parameter for generator designers and motors. P_c value determines the magnet's operating point.

Table 11: Physics of underwater searching
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%

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

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 wall, the magnet holds merely a fraction of its perpendicular strength.

2. Plate thickness effect

*Thin metal sheet (e.g. computer case) severely limits the holding force.

3. Thermal stability

*For N38 material, 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 and environmental data

Material specification

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: 030333-2026

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The ring magnet with a hole MP 20x8/4x5 / N38 is created for mechanical fastening, 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. 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. The flat screw head should evenly press the magnet. 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 does not ensure full waterproofing. 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.

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.

The presented product is a ring magnet with dimensions Ø20 mm (outer diameter) and height 5 mm. The pulling force of this model is an impressive 6.65 kg, which translates to 65.21 N in newtons. 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.

Advantages as well as disadvantages of rare earth magnets.

Pros

In addition to their magnetic capacity, neodymium magnets provide the following advantages:

Their power remains stable, and after approximately 10 years it drops only by ~1% (according to research),
They are noted for resistance to demagnetization induced by external field influence,
A magnet with a metallic nickel surface looks better,
They show high magnetic induction at the operating surface, making them more effective,
Neodymium magnets are characterized by extremely high magnetic induction on the magnet surface and can work (depending on the form) even at a temperature of 230°C or more...
Thanks to the ability of accurate forming and customization to individualized projects, NdFeB magnets can be modeled in a wide range of forms and dimensions, which makes them more universal,
Significant place in advanced technology sectors – they are used in magnetic memories, electric motors, medical equipment, as well as industrial machines.
Compactness – despite small sizes they generate large force, making them ideal for precision applications

Disadvantages

Disadvantages of NdFeB magnets:

At strong impacts they can break, therefore we advise placing them in strong housings. A metal housing provides additional protection against damage and increases the magnet's durability.
We warn that neodymium magnets can lose their power at high temperatures. To prevent this, we advise our specialized [AH] magnets, which work effectively even at 230°C.
When exposed to humidity, magnets start to rust. For applications outside, it is recommended to use protective magnets, such as those in rubber or plastics, which prevent oxidation as well as corrosion.
We suggest a housing - magnetic holder, due to difficulties in realizing nuts inside the magnet and complex shapes.
Potential hazard resulting from small fragments of magnets are risky, in case of ingestion, which becomes key in the context of child health protection. Additionally, small elements of these devices are able to disrupt the diagnostic process medical after entering the body.
Due to neodymium price, their price exceeds standard values,

Holding force characteristics

Maximum lifting capacity of the magnet – what contributes to it?

The load parameter shown represents the limit force, measured under ideal test conditions, meaning:

with the contact of a sheet made of low-carbon steel, ensuring maximum field concentration
with a thickness no less than 10 mm
with a plane cleaned and smooth
with direct contact (no impurities)
for force acting at a right angle (pull-off, not shear)
at conditions approx. 20°C

Impact of factors on magnetic holding capacity in practice

Real force impacted by working environment parameters, including (from priority):

Distance – existence of any layer (rust, tape, gap) acts as an insulator, which reduces power steeply (even by 50% at 0.5 mm).
Load vector – highest force is available only during perpendicular pulling. The shear force of the magnet along the surface is usually several times lower (approx. 1/5 of the lifting capacity).
Base massiveness – insufficiently thick plate does not close the flux, causing part of the power to be wasted to the other side.
Material composition – not every steel reacts the same. High carbon content weaken the attraction effect.
Surface finish – full contact is obtained only on smooth steel. Rough texture reduce the real contact area, weakening the magnet.
Thermal environment – heating the magnet results in weakening of induction. It is worth remembering the maximum operating temperature for a given model.

Lifting capacity was measured with the use of a smooth steel plate of optimal thickness (min. 20 mm), under perpendicular pulling force, in contrast under shearing force the load capacity is reduced by as much as fivefold. Additionally, even a small distance between the magnet’s surface and the plate lowers the holding force.

Safety rules for work with neodymium magnets

Handling guide

Before use, read the rules. Uncontrolled attraction can break the magnet or injure your hand. Be predictive.

Precision electronics

A powerful magnetic field negatively affects the operation of compasses in smartphones and navigation systems. Do not bring magnets near a device to prevent breaking the sensors.

Do not overheat magnets

Keep cool. Neodymium magnets are sensitive to heat. If you need operation above 80°C, inquire about HT versions (H, SH, UH).

Dust explosion hazard

Fire warning: Rare earth powder is highly flammable. Avoid machining magnets in home conditions as this risks ignition.

Bone fractures

Big blocks can break fingers in a fraction of a second. Under no circumstances place your hand between two strong magnets.

Avoid contact if allergic

Studies show that nickel (standard magnet coating) is a potent allergen. If your skin reacts to metals, prevent touching magnets with bare hands and choose versions in plastic housing.

Protective goggles

Beware of splinters. Magnets can fracture upon violent connection, ejecting shards into the air. We recommend safety glasses.

Protect data

Do not bring magnets near a wallet, computer, or TV. The magnetic field can irreversibly ruin these devices and wipe information from cards.

Swallowing risk

Absolutely keep magnets out of reach of children. Ingestion danger is high, and the effects of magnets clamping inside the body are life-threatening.

Medical interference

For implant holders: Powerful magnets disrupt electronics. Keep at least 30 cm distance or request help to handle the magnets.

Attention! Need more info? Read our article: Why are neodymium magnets dangerous?

MP 20x8/4x5 / N38 - ring magnet

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

Magnetic properties of material N38

Physical properties of sintered neodymium magnets Nd2Fe14B at 20°C

Engineering analysis of the product - report

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

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

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

Table 4: Steel thickness (substrate influence) - power losses MP 20x8/4x5 / N38

Table 5: Thermal resistance (material behavior) - resistance threshold MP 20x8/4x5 / N38

Table 6: Two magnets (repulsion) - field collision MP 20x8/4x5 / N38

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

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

Table 9: Surface protection spec MP 20x8/4x5 / N38

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

Table 11: Physics of underwater searching MP 20x8/4x5 / N38

1. Shear force

2. Plate thickness effect

3. Thermal stability

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

Material specification

Ecology and recycling (GPSR)

Force (pull)

Field Strength

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Advantages as well as disadvantages of rare earth magnets.

Pros

Disadvantages

Holding force characteristics

Maximum lifting capacity of the magnet – what contributes to it?

Impact of factors on magnetic holding capacity in practice

Safety rules for work with neodymium magnets

Handling guide

Precision electronics

Do not overheat magnets

Dust explosion hazard

Bone fractures

Avoid contact if allergic

Protective goggles

Protect data

Swallowing risk

Medical interference

Physical properties of sintered neodymium magnets Nd₂Fe₁₄B at 20°C

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

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

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

Table 4: Steel thickness (substrate influence) - power losses
MP 20x8/4x5 / N38

Table 5: Thermal resistance (material behavior) - resistance threshold
MP 20x8/4x5 / N38

Table 6: Two magnets (repulsion) - field collision
MP 20x8/4x5 / N38

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

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

Table 9: Surface protection spec
MP 20x8/4x5 / N38

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

Table 11: Physics of underwater searching
MP 20x8/4x5 / N38