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MP 25x8x20 / 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 030450

GTIN/EAN: 5906301812340

5.00

Diameter

25 mm [±0,1 mm]

internal diameter Ø

8 mm [±0,1 mm]

Height

20 mm [±0,1 mm]

Weight

66.09 g

Magnetization Direction

↑ axial

Load capacity

19.02 kg / 186.54 N

Magnetic Induction

525.50 mT / 5255 Gs

Coating

[NiCuNi] Nickel

check properties »

41.71 ZŁ with VAT / pcs + price for transport

33.91 ZŁ net + 23% VAT / pcs

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Technical - MP 25x8x20 / N38 - ring magnet

Specification / characteristics - MP 25x8x20 / N38 - ring magnet

properties

properties	values
Cat. no.	030450
GTIN/EAN	5906301812340
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	8 mm [±0,1 mm]
Height	20 mm [±0,1 mm]
Weight	66.09 g
Magnetization Direction	↑ axial
Load capacity ~ ?	19.02 kg / 186.54 N
Magnetic Induction ~ ?	525.50 mT / 5255 Gs
Coating	[NiCuNi] Nickel
Manufacturing Tolerance	±0.1 mm

Magnetic properties of material N38

Specification / characteristics MP 25x8x20 / N38 - ring magnet

properties	values	units
remenance Br [min. - max.] ?	12.2-12.6	kGs
remenance Br [min. - max.] ?	1220-1260	mT
coercivity bHc ?	10.8-11.5	kOe
coercivity bHc ?	860-915	kA/m
actual internal force iHc	≥ 12	kOe
actual internal force iHc	≥ 955	kA/m
energy density [min. - max.] ?	36-38	BH max MGOe
energy density [min. - max.] ?	287-303	BH max KJ/m
max. temperature ?	≤ 80	°C

Physical properties of sintered neodymium magnets Nd₂Fe₁₄B at 20°C

properties	values	units
Vickers hardness	≥550	Hv
Density	≥7.4	g/cm³
Curie Temperature TC	312 - 380	°C
Curie Temperature TF	593 - 716	°F
Specific resistance	150	μΩ⋅cm
Bending strength	250	MPa
Compressive strength	1000~1100	MPa
Thermal expansion parallel (∥) to orientation (M)	(3-4) x 10^-6	°C^-1
Thermal expansion perpendicular (⊥) to orientation (M)	-(1-3) x 10^-6	°C^-1
Young's modulus	1.7 x 10⁴	kg/mm²

Engineering modeling of the magnet - report

These information represent the outcome of a physical simulation. Values were calculated on algorithms for the class Nd₂Fe₁₄B. Real-world parameters might slightly differ. Use these calculations as a supplementary guide when designing systems.

Table 1: Static force (force vs distance) - interaction chart
MP 25x8x20 / N38

Distance (mm)	Induction (Gauss) / mT	Pull Force (kg/lbs/g/N)	Risk Status
0 mm	5777 Gs 577.7 mT	19.02 kg / 41.93 LBS 19020.0 g / 186.6 N	critical level
1 mm	5310 Gs 531.0 mT	16.07 kg / 35.42 LBS 16067.7 g / 157.6 N	critical level
2 mm	4846 Gs 484.6 mT	13.38 kg / 29.50 LBS 13380.1 g / 131.3 N	critical level
3 mm	4397 Gs 439.7 mT	11.02 kg / 24.29 LBS 11019.3 g / 108.1 N	critical level
5 mm	3576 Gs 357.6 mT	7.29 kg / 16.07 LBS 7287.1 g / 71.5 N	warning
10 mm	2073 Gs 207.3 mT	2.45 kg / 5.40 LBS 2448.1 g / 24.0 N	warning
15 mm	1231 Gs 123.1 mT	0.86 kg / 1.90 LBS 863.8 g / 8.5 N	weak grip
20 mm	773 Gs 77.3 mT	0.34 kg / 0.75 LBS 340.1 g / 3.3 N	weak grip
30 mm	356 Gs 35.6 mT	0.07 kg / 0.16 LBS 72.1 g / 0.7 N	weak grip
50 mm	115 Gs 11.5 mT	0.01 kg / 0.02 LBS 7.5 g / 0.1 N	weak grip

Grip strength weakens significantly with every subsequent millimeter of gap. Keep in mind that even a very thin break (e.g., dirt, varnish, veneer) noticeably weakens the grip. Magnets hold most effectively at the point of direct contact; distance nullifies the force. Analyze how quickly the load capacity drop, when the product does not touch directly to the steel surface. When calculating the arrangement, avoid redundant distances.

Table 2: Shear load (vertical surface)
MP 25x8x20 / N38

Distance (mm)	Friction coefficient	Pull Force (kg/lbs/g/N)
0 mm	Stal (~0.2)	3.80 kg / 8.39 LBS 3804.0 g / 37.3 N
1 mm	Stal (~0.2)	3.21 kg / 7.09 LBS 3214.0 g / 31.5 N
2 mm	Stal (~0.2)	2.68 kg / 5.90 LBS 2676.0 g / 26.3 N
3 mm	Stal (~0.2)	2.20 kg / 4.86 LBS 2204.0 g / 21.6 N
5 mm	Stal (~0.2)	1.46 kg / 3.21 LBS 1458.0 g / 14.3 N
10 mm	Stal (~0.2)	0.49 kg / 1.08 LBS 490.0 g / 4.8 N
15 mm	Stal (~0.2)	0.17 kg / 0.38 LBS 172.0 g / 1.7 N
20 mm	Stal (~0.2)	0.07 kg / 0.15 LBS 68.0 g / 0.7 N
30 mm	Stal (~0.2)	0.01 kg / 0.03 LBS 14.0 g / 0.1 N
50 mm	Stal (~0.2)	0.00 kg / 0.00 LBS 2.0 g / 0.0 N

The following data calculates the approximate holding capacity sufficient to initiate the slippage of the magnet vertically on a upright steel plate (assuming typical friction coefficient). This parameter varies with the gap size between the magnet and the surface.

Table 3: Wall mounting (sliding) - behavior on slippery surfaces
MP 25x8x20 / N38

Surface type	Friction coefficient / % Mocy	Max load (kg/lbs/g/N)
Raw steel	µ = 0.3 30% Nominalnej Siły	5.71 kg / 12.58 LBS 5706.0 g / 56.0 N
Painted steel (standard)	µ = 0.2 20% Nominalnej Siły	3.80 kg / 8.39 LBS 3804.0 g / 37.3 N
Oily/slippery steel	µ = 0.1 10% Nominalnej Siły	1.90 kg / 4.19 LBS 1902.0 g / 18.7 N
Magnet with anti-slip rubber	µ = 0.5 50% Nominalnej Siły	9.51 kg / 20.97 LBS 9510.0 g / 93.3 N

When placing a holder on a upright wall (e.g., a car body), it you can count on barely about 20%-30% of its maximum pull force. Gravitational force as well as a low friction coefficient influence the fact that holders slip faster than they pop off the substrate. Planning a vertical fastening? Note that the shear force is significantly lower than the perpendicular breakaway force. On a painted metal, the holder will slide down under a much lighter weight. Application of an anti-slip layer can effectively increase the grip.

Table 4: Steel thickness (substrate influence) - power losses
MP 25x8x20 / N38

Steel thickness (mm)	% power	Real pull force (kg/lbs/g/N)
0.5 mm	5%	0.95 kg / 2.10 LBS 951.0 g / 9.3 N
1 mm	13%	2.38 kg / 5.24 LBS 2377.5 g / 23.3 N
2 mm	25%	4.76 kg / 10.48 LBS 4755.0 g / 46.6 N
3 mm	38%	7.13 kg / 15.72 LBS 7132.5 g / 70.0 N
5 mm	63%	11.89 kg / 26.21 LBS 11887.5 g / 116.6 N
10 mm	100%	19.02 kg / 41.93 LBS 19020.0 g / 186.6 N
11 mm	100%	19.02 kg / 41.93 LBS 19020.0 g / 186.6 N
12 mm	100%	19.02 kg / 41.93 LBS 19020.0 g / 186.6 N

A thin sheet cannot absorb the entire magnetic field, which weakens actual performance of the magnet. Should you attach a powerful product to a thin surface, the flux will pass right through and the pull force will drop sharply. To squeeze the maximum of this neodymium's power, you require a sufficiently solid element of metal. The saturation phenomenon causes that on thin elements (e.g., car bodies), the product holds weaker. We advise picking the steel thickness from these parameters.

Table 5: Working in heat (material behavior) - power drop
MP 25x8x20 / N38

Ambient temp. (°C)	Power loss	Remaining pull (kg/lbs/g/N)	Status
20 °C	0.0%	19.02 kg / 41.93 LBS 19020.0 g / 186.6 N	OK
40 °C	-2.2%	18.60 kg / 41.01 LBS 18601.6 g / 182.5 N	OK
60 °C	-4.4%	18.18 kg / 40.09 LBS 18183.1 g / 178.4 N	OK
80 °C	-6.6%	17.76 kg / 39.16 LBS 17764.7 g / 174.3 N
100 °C	-28.8%	13.54 kg / 29.86 LBS 13542.2 g / 132.8 N

Ordinary NdFeB products change their properties parameters past the thermal threshold. Protect against heat – high temperature can irreversibly destroy this product. With every degree above norm, the magnet's capacity temporarily decreases. Refrain from using this magnet in hot environments exceeding its safe range. Exceeding the critical threshold will cause irreversible degradation of magnetic properties.

*Technical advisory: Temperature resistance is determined by both grade, and the Permeance Coefficient Pc. Flat magnets (low permeance coefficient) are more susceptible to demagnetization under lower heat stress than long magnets. The danger warning in the table indicates permanent field degradation for this particular item.

Table 6: Magnet-Magnet interaction (attraction) - forces in the system
MP 25x8x20 / N38

Gap (mm)	Attraction (kg/lbs) (N-S)	Shear Strength (kg/lbs/g/N)	Repulsion (kg/lbs) (N-N)
0 mm	30.91 kg / 68.14 LBS 6 082 Gs	4.64 kg / 10.22 LBS 4636 g / 45.5 N	N/A
1 mm	28.48 kg / 62.79 LBS 11 091 Gs	4.27 kg / 9.42 LBS 4272 g / 41.9 N	25.63 kg / 56.51 LBS ~0 Gs
2 mm	26.11 kg / 57.57 LBS 10 620 Gs	3.92 kg / 8.63 LBS 3917 g / 38.4 N	23.50 kg / 51.81 LBS ~0 Gs
3 mm	23.86 kg / 52.61 LBS 10 153 Gs	3.58 kg / 7.89 LBS 3580 g / 35.1 N	21.48 kg / 47.35 LBS ~0 Gs
5 mm	19.76 kg / 43.56 LBS 9 238 Gs	2.96 kg / 6.53 LBS 2964 g / 29.1 N	17.78 kg / 39.20 LBS ~0 Gs
10 mm	11.84 kg / 26.11 LBS 7 152 Gs	1.78 kg / 3.92 LBS 1776 g / 17.4 N	10.66 kg / 23.50 LBS ~0 Gs
20 mm	3.98 kg / 8.77 LBS 4 145 Gs	0.60 kg / 1.32 LBS 597 g / 5.9 N	3.58 kg / 7.89 LBS ~0 Gs
50 mm	0.24 kg / 0.54 LBS 1 024 Gs	0.04 kg / 0.08 LBS 36 g / 0.4 N	0.22 kg / 0.48 LBS ~0 Gs
60 mm	0.12 kg / 0.26 LBS 712 Gs	0.02 kg / 0.04 LBS 18 g / 0.2 N	0.11 kg / 0.23 LBS ~0 Gs
70 mm	0.06 kg / 0.13 LBS 514 Gs	0.01 kg / 0.02 LBS 9 g / 0.1 N	0.06 kg / 0.12 LBS ~0 Gs
80 mm	0.03 kg / 0.07 LBS 383 Gs	0.01 kg / 0.01 LBS 5 g / 0.1 N	0.03 kg / 0.07 LBS ~0 Gs
90 mm	0.02 kg / 0.04 LBS 293 Gs	0.00 kg / 0.01 LBS 3 g / 0.0 N	0.02 kg / 0.04 LBS ~0 Gs
100 mm	0.01 kg / 0.03 LBS 230 Gs	0.00 kg / 0.00 LBS 2 g / 0.0 N	0.01 kg / 0.02 LBS ~0 Gs

Two magnets attract each other from a wider radius than a magnet and steel setup. The connection of magnet-to-magnet generates a stronger field and a larger range of performance. Want to build a powerful holder? Use a pair of magnets instead of one magnet and a steel. Be careful that when connecting a pair of magnets, the pinch force is extreme. The repulsion force is slightly lower than the attraction, but still significant.
*Field value between like poles reaches ~0 Gs at the midpoint of the gap (caused by magnetic field nullification).
Important: Calculations show friction force of a pair of matching magnets (friction coefficient ~0.15 for Ni-Ni coating).

Table 7: Protective zones (implants) - warnings
MP 25x8x20 / N38

Object / Device	Limit (Gauss) / mT	Safe distance
Pacemaker	5 Gs (0.5 mT)	17.0 cm
Hearing aid	10 Gs (1.0 mT)	13.5 cm
Timepiece	20 Gs (2.0 mT)	10.5 cm
Phone / Smartphone	40 Gs (4.0 mT)	8.0 cm
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

Extremely neodym field poses a large risk to electronics as well as pacemakers. These magnets generate a field that prevents correct functioning of sensitive medical devices. Notice: the invisible magnetic field passes through tissues and glass. Exceptional care must be taken by people with cochlear implants and drug dispensers. Also at risk are: automatic timepieces, remotes, speakers, and displays. Do not bring the product near payment cards, hard drives, or precise measuring instruments.

Table 8: Dynamics (kinetic energy) - warning
MP 25x8x20 / N38

Start from (mm)	Speed (km/h)	Energy (J)
10 mm	18.43 km/h (5.12 m/s)	0.87 J
30 mm	29.70 km/h (8.25 m/s)	2.25 J
50 mm	38.27 km/h (10.63 m/s)	3.73 J
100 mm	54.10 km/h (15.03 m/s)	7.46 J

NdFeB products are prone to chipping – a violent impact against metal causes immediate chipping. Control the attraction moment – a neodymium left loose becomes dangerous. Kinetic force can cause material chips or dangerous crushing to skin. Always hold the magnet during bringing near metal so it doesn't hit violently against the steel surface. A contact at a velocity of dozens of km/h ends with a crack of the magnet. Wear eye protection when handling with large magnets.

Table 9: Anti-corrosion coating durability
MP 25x8x20 / 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 25x8x20 / N38

Parameter	Value	SI Unit / Description
Magnetic Flux	10 108 Mx	101.1 µWb
P_c Coefficient	1.25	High (Stable)

Flux value emitted by the magnet pole. Essential parameter for generator designers as well as sensors. The P_c coefficient defines the working geometry.

Table 11: Physics of underwater searching
MP 25x8x20 / N38

Environment	Effective steel pull	Effect
Air (land)	19.02 kg	Standard
Water (riverbed)	21.78 kg (+2.76 kg buoyancy gain)	+14.5%

Warning: This magnet has a standard nickel coating. After use in water, it must be dried and maintained immediately, otherwise it will rust!

Water displaces steel, making heavy objects slightly lighter. As a result, your magnet will pull a heavier object from the bottom than if you lifted it in the air.

1. Wall mount (shear)

*Warning: On a vertical wall, the magnet retains merely ~20% of its nominal pull.

2. Plate thickness effect

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

3. Power loss vs temp

*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) = 1.25

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: 030450-2026

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MPL 30x20x20 / N38 - lamellar magnet

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24.60 ZŁ brutto / pcs

The ring-shaped magnet MP 25x8x20 / 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 19.02 kg works great as a door latch, 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 caution. 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.

These magnets are coated with standard Ni-Cu-Ni plating, which protects them in indoor conditions, but does not ensure full waterproofing. In the place of the mounting hole, the coating is thinner and easily scratched when tightening the screw, which will become a corrosion focus. This product is dedicated for indoor use. For outdoor applications, we recommend choosing rubberized holders or additional protection with varnish.

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 (25 mm), so it doesn't protrude beyond the outline.

The presented product is a ring magnet with dimensions Ø25 mm (outer diameter) and height 20 mm. The key parameter here is the holding force amounting to approximately 19.02 kg (force ~186.54 N). The mounting hole diameter is precisely 8 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.

Advantages as well as disadvantages of Nd₂Fe₁₄B magnets.

Pros

Besides their immense field intensity, neodymium magnets offer the following advantages:

They have constant strength, and over more than ten years their attraction force decreases symbolically – ~1% (in testing),
They are resistant to demagnetization induced by external disturbances,
In other words, due to the smooth layer of silver, the element looks attractive,
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 work (depending on the shape) even at a temperature of 230°C or more...
Thanks to versatility in designing and the capacity to customize to client solutions,
Significant place in modern industrial fields – they serve a role in mass storage devices, motor assemblies, advanced medical instruments, also modern systems.
Compactness – despite small sizes they offer powerful magnetic field, making them ideal for precision applications

Cons

Disadvantages of NdFeB magnets:

They are prone to damage upon too strong impacts. To avoid cracks, it is worth protecting magnets using a steel holder. Such protection not only protects the magnet but also increases its resistance to damage
We warn that neodymium magnets can lose their power at high temperatures. To prevent this, we recommend our specialized [AH] magnets, which work effectively even at 230°C.
Due to the susceptibility of magnets to corrosion in a humid environment, we recommend using waterproof magnets made of rubber, plastic or other material resistant to moisture, in case of application outdoors
We recommend casing - magnetic holder, due to difficulties in creating nuts inside the magnet and complicated shapes.
Possible danger related to microscopic parts of magnets can be dangerous, in case of ingestion, which gains importance in the context of child health protection. It is also worth noting that small elements of these devices can disrupt the diagnostic process medical when they are in the body.
Due to expensive raw materials, their price exceeds standard values,

Pull force analysis

Maximum magnetic pulling force – what affects it?

The declared magnet strength refers to the peak performance, obtained under laboratory conditions, meaning:

using a plate made of low-carbon steel, functioning as a magnetic yoke
with a cross-section minimum 10 mm
characterized by even structure
under conditions of no distance (metal-to-metal)
during pulling in a direction perpendicular to the plane
at conditions approx. 20°C

Determinants of lifting force in real conditions

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

Space between magnet and steel – every millimeter of distance (caused e.g. by veneer or unevenness) drastically reduces the pulling force, often by half at just 0.5 mm.
Pull-off angle – remember that the magnet holds strongest perpendicularly. Under sliding down, the holding force drops significantly, often to levels of 20-30% of the nominal value.
Element thickness – for full efficiency, the steel must be sufficiently thick. Thin sheet restricts the attraction force (the magnet "punches through" it).
Steel grade – ideal substrate is pure iron steel. Hardened steels may attract less.
Surface quality – the more even the plate, the larger the contact zone and higher the lifting capacity. Roughness creates an air distance.
Operating temperature – NdFeB sinters have a negative temperature coefficient. When it is hot they are weaker, and in frost gain strength (up to a certain limit).

Holding force was checked on the plate surface of 20 mm thickness, when the force acted perpendicularly, however under attempts to slide the magnet the holding force is lower. Moreover, even a slight gap between the magnet and the plate decreases the lifting capacity.

Safety rules for work with NdFeB magnets

Eye protection

Neodymium magnets are sintered ceramics, meaning they are prone to chipping. Clashing of two magnets leads to them shattering into small pieces.

Operating temperature

Control the heat. Heating the magnet to high heat will destroy its properties and pulling force.

GPS Danger

A strong magnetic field interferes with the functioning of compasses in smartphones and GPS navigation. Keep magnets close to a smartphone to prevent breaking the sensors.

Nickel coating and allergies

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

Do not give to children

Product intended for adults. Small elements pose a choking risk, causing severe trauma. Store away from kids and pets.

Keep away from computers

Device Safety: Strong magnets can damage payment cards and delicate electronics (heart implants, hearing aids, timepieces).

Life threat

Patients with a heart stimulator have to keep an large gap from magnets. The magnetic field can interfere with the functioning of the life-saving device.

Dust explosion hazard

Fire warning: Rare earth powder is highly flammable. Avoid machining magnets without safety gear as this risks ignition.

Do not underestimate power

Use magnets with awareness. Their immense force can surprise even professionals. Plan your moves and respect their force.

Bone fractures

Danger of trauma: The pulling power is so immense that it can result in hematomas, crushing, and broken bones. Use thick gloves.

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

MP 25x8x20 / N38 - ring magnet

Technical - MP 25x8x20 / N38 - ring magnet

Magnetic properties of material N38

Physical properties of sintered neodymium magnets Nd2Fe14B at 20°C

Engineering modeling of the magnet - report

Table 1: Static force (force vs distance) - interaction chart MP 25x8x20 / N38

Table 2: Shear load (vertical surface) MP 25x8x20 / N38

Table 3: Wall mounting (sliding) - behavior on slippery surfaces MP 25x8x20 / N38

Table 4: Steel thickness (substrate influence) - power losses MP 25x8x20 / N38

Table 5: Working in heat (material behavior) - power drop MP 25x8x20 / N38

Table 6: Magnet-Magnet interaction (attraction) - forces in the system MP 25x8x20 / N38

Table 7: Protective zones (implants) - warnings MP 25x8x20 / N38

Table 8: Dynamics (kinetic energy) - warning MP 25x8x20 / N38

Table 9: Anti-corrosion coating durability MP 25x8x20 / N38

Table 10: Electrical data (Flux) MP 25x8x20 / N38

Table 11: Physics of underwater searching MP 25x8x20 / N38

1. Wall mount (shear)

2. Plate thickness effect

3. Power loss vs temp

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

Elemental analysis

Environmental data

Magnet pull force

Magnetic Induction

See also offers

MPL 30x20x20 / N38 - lamellar magnet

MP 36.2x11/6x7.5 / N38 - ring magnet

UMP 97x40 [M8+M10] GW F300 Lina / N38 - search holder

KM HF - 11,3 kg - magnetic bracket

Advantages as well as disadvantages of Nd2Fe14B magnets.

Pros

Cons

Pull force analysis

Maximum magnetic pulling force – what affects it?

Determinants of lifting force in real conditions

Safety rules for work with NdFeB magnets

Eye protection

Operating temperature

GPS Danger

Nickel coating and allergies

Do not give to children

Keep away from computers

Life threat

Dust explosion hazard

Do not underestimate power

Bone fractures

Physical properties of sintered neodymium magnets Nd₂Fe₁₄B at 20°C

Table 1: Static force (force vs distance) - interaction chart
MP 25x8x20 / N38

Table 2: Shear load (vertical surface)
MP 25x8x20 / N38

Table 3: Wall mounting (sliding) - behavior on slippery surfaces
MP 25x8x20 / N38

Table 4: Steel thickness (substrate influence) - power losses
MP 25x8x20 / N38

Table 5: Working in heat (material behavior) - power drop
MP 25x8x20 / N38

Table 6: Magnet-Magnet interaction (attraction) - forces in the system
MP 25x8x20 / N38

Table 7: Protective zones (implants) - warnings
MP 25x8x20 / N38

Table 8: Dynamics (kinetic energy) - warning
MP 25x8x20 / N38

Table 9: Anti-corrosion coating durability
MP 25x8x20 / N38

Table 10: Electrical data (Flux)
MP 25x8x20 / N38

Table 11: Physics of underwater searching
MP 25x8x20 / N38

Advantages as well as disadvantages of Nd₂Fe₁₄B magnets.