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MP 25x13x4 / N38 - ring magnet

Name: Dhit sp. z o.o.
Address: Kościuszki 6A, Ożarów Mazowiecki, Poland, 05-850, PL
Telephone: +48 22 499 98 98
Price range: PLN 1-6500
Rating: 5

ring magnet

Catalog no 030190

GTIN/EAN: 5906301812074

5.00

Diameter

25 mm [±0,1 mm]

internal diameter Ø

13 mm [±0,1 mm]

Height

4 mm [±0,1 mm]

Weight

10.74 g

Magnetization Direction

↑ axial

Load capacity

4.14 kg / 40.57 N

Magnetic Induction

188.92 mT / 1889 Gs

Coating

[NiCuNi] Nickel

see properties »

6.77 ZŁ with VAT / pcs + price for transport

5.50 ZŁ net + 23% VAT / pcs

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Carbon Footprint – environmental impact GPSR Regulation – product safety

Want to talk magnets?

Call us +48 888 99 98 98 or contact us by means of our online form the contact page.
Parameters along with appearance of neodymium magnets can be calculated using our online calculation tool.

Orders placed before 14:00 will be shipped the same business day.

Technical specification of the product - MP 25x13x4 / N38 - ring magnet

Specification / characteristics - MP 25x13x4 / N38 - ring magnet

properties

properties	values
Cat. no.	030190
GTIN/EAN	5906301812074
Production/Distribution	Dhit sp. z o.o. ul. Zielona 14 05-850 Ożarów Mazowiecki PL
Country of origin	Poland / China / Germany
Customs code	85059029
Diameter	25 mm [±0,1 mm]
internal diameter Ø	13 mm [±0,1 mm]
Height	4 mm [±0,1 mm]
Weight	10.74 g
Magnetization Direction	↑ axial
Load capacity ~ ?	4.14 kg / 40.57 N
Magnetic Induction ~ ?	188.92 mT / 1889 Gs
Coating	[NiCuNi] Nickel
Manufacturing Tolerance	±0.1 mm

Magnetic properties of material N38

Specification / characteristics MP 25x13x4 / N38 - ring magnet

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

Physical properties of sintered neodymium magnets Nd₂Fe₁₄B at 20°C

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

Engineering modeling of the product - technical parameters

Presented values represent the direct effect of a mathematical simulation. Results are based on algorithms for the material Nd₂Fe₁₄B. Real-world performance might slightly deviate from the simulation results. Treat these data as a reference point during assembly planning.

Table 1: Static force (force vs distance) - interaction chart
MP 25x13x4 / N38

Distance (mm)	Induction (Gauss) / mT	Pull Force (kg/lbs/g/N)	Risk Status
0 mm	5777 Gs 577.7 mT	4.14 kg / 9.13 pounds 4140.0 g / 40.6 N	medium risk
1 mm	5310 Gs 531.0 mT	3.50 kg / 7.71 pounds 3497.4 g / 34.3 N	medium risk
2 mm	4846 Gs 484.6 mT	2.91 kg / 6.42 pounds 2912.4 g / 28.6 N	medium risk
3 mm	4397 Gs 439.7 mT	2.40 kg / 5.29 pounds 2398.5 g / 23.5 N	medium risk
5 mm	3576 Gs 357.6 mT	1.59 kg / 3.50 pounds 1586.2 g / 15.6 N	safe
10 mm	2073 Gs 207.3 mT	0.53 kg / 1.17 pounds 532.9 g / 5.2 N	safe
15 mm	1231 Gs 123.1 mT	0.19 kg / 0.41 pounds 188.0 g / 1.8 N	safe
20 mm	773 Gs 77.3 mT	0.07 kg / 0.16 pounds 74.0 g / 0.7 N	safe
30 mm	356 Gs 35.6 mT	0.02 kg / 0.03 pounds 15.7 g / 0.2 N	safe
50 mm	115 Gs 11.5 mT	0.00 kg / 0.00 pounds 1.6 g / 0.0 N	safe

Grip strength decreases drastically with every mm of spacing. Note that even the smallest gap (e.g., dirt, varnish, veneer) noticeably diminishes the holding power. Magnetic products operate most effectively at the point of direct contact; distance kills the power. Notice how rapidly the pull force fall, when the magnet does not touch flatly to the metal substrate. When planning the arrangement, avoid unnecessary gaps.

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

Distance (mm)	Friction coefficient	Pull Force (kg/lbs/g/N)
0 mm	Stal (~0.2)	0.83 kg / 1.83 pounds 828.0 g / 8.1 N
1 mm	Stal (~0.2)	0.70 kg / 1.54 pounds 700.0 g / 6.9 N
2 mm	Stal (~0.2)	0.58 kg / 1.28 pounds 582.0 g / 5.7 N
3 mm	Stal (~0.2)	0.48 kg / 1.06 pounds 480.0 g / 4.7 N
5 mm	Stal (~0.2)	0.32 kg / 0.70 pounds 318.0 g / 3.1 N
10 mm	Stal (~0.2)	0.11 kg / 0.23 pounds 106.0 g / 1.0 N
15 mm	Stal (~0.2)	0.04 kg / 0.08 pounds 38.0 g / 0.4 N
20 mm	Stal (~0.2)	0.01 kg / 0.03 pounds 14.0 g / 0.1 N
30 mm	Stal (~0.2)	0.00 kg / 0.01 pounds 4.0 g / 0.0 N
50 mm	Stal (~0.2)	0.00 kg / 0.00 pounds 0.0 g / 0.0 N

This section calculates the theoretical holding capacity required to initiate the downward movement of the magnet vertically along a upright steel wall (considering standard friction coefficient). The holding force is a function of the gap size between the magnet and the metal.

Table 3: Wall mounting (sliding) - behavior on slippery surfaces
MP 25x13x4 / N38

Surface type	Friction coefficient / % Mocy	Max load (kg/lbs/g/N)
Raw steel	µ = 0.3 30% Nominalnej Siły	1.24 kg / 2.74 pounds 1242.0 g / 12.2 N
Painted steel (standard)	µ = 0.2 20% Nominalnej Siły	0.83 kg / 1.83 pounds 828.0 g / 8.1 N
Oily/slippery steel	µ = 0.1 10% Nominalnej Siły	0.41 kg / 0.91 pounds 414.0 g / 4.1 N
Magnet with anti-slip rubber	µ = 0.5 50% Nominalnej Siły	2.07 kg / 4.56 pounds 2070.0 g / 20.3 N

When mounting a element on a upright plane (e.g., a board), it you can count on barely approx. 20%-30% of its maximum pull force. Gravity as well as a low friction coefficient influence the fact that holders move down easier than they detach. Want to create a wall mount? Note that the shear force is noticeably lower than the maximum static pull force. On a painted metal, the holder will give way down under a significantly smaller load. Using a rubber pad can drastically raise the stability.

Table 4: Steel thickness (saturation) - power losses
MP 25x13x4 / N38

Steel thickness (mm)	% power	Real pull force (kg/lbs/g/N)
0.5 mm	10%	0.41 kg / 0.91 pounds 414.0 g / 4.1 N
1 mm	25%	1.04 kg / 2.28 pounds 1035.0 g / 10.2 N
2 mm	50%	2.07 kg / 4.56 pounds 2070.0 g / 20.3 N
3 mm	75%	3.10 kg / 6.85 pounds 3105.0 g / 30.5 N
5 mm	100%	4.14 kg / 9.13 pounds 4140.0 g / 40.6 N
10 mm	100%	4.14 kg / 9.13 pounds 4140.0 g / 40.6 N
11 mm	100%	4.14 kg / 9.13 pounds 4140.0 g / 40.6 N
12 mm	100%	4.14 kg / 9.13 pounds 4140.0 g / 40.6 N

A thin sheet cannot take in the entire magnetic field, which weakens actual performance of the magnet. Should you install a neodymium to a thin surface, the field will pass right through and the holding will be smaller. To achieve 100% of this neodymium's potential, you need a suitably thick piece of steel. The material oversaturation means that on thin elements (e.g., appliance housings), the holder shows lower pull force. We suggest choosing the steel thickness from these parameters.

Table 5: Thermal stability (material behavior) - thermal limit
MP 25x13x4 / N38

Ambient temp. (°C)	Power loss	Remaining pull (kg/lbs/g/N)	Status
20 °C	0.0%	4.14 kg / 9.13 pounds 4140.0 g / 40.6 N	OK
40 °C	-2.2%	4.05 kg / 8.93 pounds 4048.9 g / 39.7 N	OK
60 °C	-4.4%	3.96 kg / 8.73 pounds 3957.8 g / 38.8 N	OK
80 °C	-6.6%	3.87 kg / 8.52 pounds 3866.8 g / 37.9 N
100 °C	-28.8%	2.95 kg / 6.50 pounds 2947.7 g / 28.9 N

Classic neodymiums change their properties parameters past the thermal threshold. Avoid high temperatures – heat can permanently demagnetize this magnet. As the temperature rises, the neodymium's capacity temporarily decreases. Refrain from using this magnet near heat sources exceeding its safe range. Ignoring the limit will result in irreversible degradation of magnetic properties.

*Engineering note: Thermal stability depends not only on the material grade, as well as the dimension ratios. Flat magnets (pancake types) are more susceptible to demagnetization at lower temperatures than taller cylinders. Warning indicator in the table indicates a risk of irreversible loss for this particular item.

Table 6: Two magnets (repulsion) - field collision
MP 25x13x4 / N38

Gap (mm)	Attraction (kg/lbs) (N-S)	Lateral Force (kg/lbs/g/N)	Repulsion (kg/lbs) (N-N)
0 mm	83.66 kg / 184.44 pounds 6 082 Gs	12.55 kg / 27.67 pounds 12549 g / 123.1 N	N/A
1 mm	77.09 kg / 169.95 pounds 11 091 Gs	11.56 kg / 25.49 pounds 11563 g / 113.4 N	69.38 kg / 152.95 pounds ~0 Gs
2 mm	70.68 kg / 155.81 pounds 10 620 Gs	10.60 kg / 23.37 pounds 10601 g / 104.0 N	63.61 kg / 140.23 pounds ~0 Gs
3 mm	64.59 kg / 142.40 pounds 10 153 Gs	9.69 kg / 21.36 pounds 9689 g / 95.0 N	58.13 kg / 128.16 pounds ~0 Gs
5 mm	53.48 kg / 117.90 pounds 9 238 Gs	8.02 kg / 17.68 pounds 8022 g / 78.7 N	48.13 kg / 106.11 pounds ~0 Gs
10 mm	32.05 kg / 70.66 pounds 7 152 Gs	4.81 kg / 10.60 pounds 4808 g / 47.2 N	28.85 kg / 63.60 pounds ~0 Gs
20 mm	10.77 kg / 23.74 pounds 4 145 Gs	1.62 kg / 3.56 pounds 1615 g / 15.8 N	9.69 kg / 21.37 pounds ~0 Gs
50 mm	0.66 kg / 1.45 pounds 1 024 Gs	0.10 kg / 0.22 pounds 99 g / 1.0 N	0.59 kg / 1.30 pounds ~0 Gs
60 mm	0.32 kg / 0.70 pounds 712 Gs	0.05 kg / 0.10 pounds 48 g / 0.5 N	0.29 kg / 0.63 pounds ~0 Gs
70 mm	0.17 kg / 0.36 pounds 514 Gs	0.02 kg / 0.05 pounds 25 g / 0.2 N	0.15 kg / 0.33 pounds ~0 Gs
80 mm	0.09 kg / 0.20 pounds 383 Gs	0.01 kg / 0.03 pounds 14 g / 0.1 N	0.08 kg / 0.18 pounds ~0 Gs
90 mm	0.05 kg / 0.12 pounds 293 Gs	0.01 kg / 0.02 pounds 8 g / 0.1 N	0.05 kg / 0.11 pounds ~0 Gs
100 mm	0.03 kg / 0.07 pounds 230 Gs	0.00 kg / 0.01 pounds 5 g / 0.0 N	0.03 kg / 0.07 pounds ~0 Gs

Two magnetic products attract each other from a wider radius than a magnet and steel combination. The connection of magnet-to-magnet generates a stronger field and a wider radius of performance. Want to build a strong closure? Apply two magnets instead of a neodymium and a striker plate. Exercise caution that when bringing together two magnets, the impact force is massive. The levitation is slightly lower than the connection force, but still impressive.
*The magnetic induction in repulsion mode drops to ~0 Gs in the exact middle of the gap (due to field cancellation).
Important: Figures refer to friction force of a pair of same neodymium magnets (friction ~0.15 for Ni-Ni coating).

Table 7: Hazards (implants) - precautionary measures
MP 25x13x4 / N38

Object / Device	Limit (Gauss) / mT	Safe distance
Pacemaker	5 Gs (0.5 mT)	17.0 cm
Hearing aid	10 Gs (1.0 mT)	13.5 cm
Mechanical watch	20 Gs (2.0 mT)	10.5 cm
Mobile device	40 Gs (4.0 mT)	8.0 cm
Car key	50 Gs (5.0 mT)	7.5 cm
Payment card	400 Gs (40.0 mT)	3.0 cm
HDD hard drive	600 Gs (60.0 mT)	2.5 cm

Powerful magnet radiation is a serious hazard to IT equipment as well as pacemakers. These magnets produce a field that destroys function of digital equipment. Be aware: the unseen radiation passes through tissues and glass. Special caution must be exercised by people with hearing aids and insulin pumps. The risk also applies to: automatic timepieces, car keys, speakers, and displays. Avoid contact with magnetic cards, hard drives, or precise measuring instruments.

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

Start from (mm)	Speed (km/h)	Energy (J)
10 mm	21.33 km/h (5.93 m/s)	0.19 J
30 mm	34.38 km/h (9.55 m/s)	0.49 J
50 mm	44.29 km/h (12.30 m/s)	0.81 J
100 mm	62.62 km/h (17.39 m/s)	1.62 J

Magnetic elements are very brittle – a collision with steel can result in shattering. Control the attraction moment – a neodymium left loose speeds with massive force. Kinetic force can destroy the magnet or painful pinches to fingers. Hold the magnet firmly during mounting so it doesn't hit violently against the steel surface. A collision at high speed almost guarantees destruction of the neodymium. Use safety goggles when playing with powerful specimens.

Table 9: Anti-corrosion coating durability
MP 25x13x4 / N38

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

For outdoor applications, an epoxy coating is required; standard nickel is intended for indoor use. Moisture resistance is crucial for installations in bathrooms or outdoors.

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

Parameter	Value	SI Unit / Description
Magnetic Flux	24 861 Mx	248.6 µWb
P_c Coefficient	1.02	High (Stable)

Flux value emitted by the magnet pole. Essential parameter in coil applications as well as sensors. The P_c coefficient defines the working geometry.

Table 11: Underwater work (magnet fishing)
MP 25x13x4 / N38

Environment	Effective steel pull	Effect
Air (land)	4.14 kg	Standard
Water (riverbed)	4.74 kg (+0.60 kg buoyancy gain)	+14.5%

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

Water displaces steel, making heavy objects slightly lighter. 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 surface, the magnet retains only approx. 20-30% of its perpendicular strength.

2. Efficiency vs thickness

*Thin metal sheet (e.g. 0.5mm PC case) drastically 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) = 1.02

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.

Engineering data and GPSR

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: 030190-2026

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The ring magnet with a hole MP 25x13x4 / 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 4.14 kg works great as a door latch, speaker holder, or spacer element in devices.

This is a crucial issue when working with model MP 25x13x4 / N38. Neodymium magnets are sintered ceramics, which means they are very brittle and inelastic. One turn too many can destroy the magnet, so do it slowly. The flat screw head should evenly press the magnet. Remember: cracking during assembly results from material properties, not a product defect.

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. This product is dedicated for inside building 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.

It is a magnetic ring with a diameter of 25 mm and thickness 4 mm. The key parameter here is the holding force amounting to approximately 4.14 kg (force ~40.57 N). The mounting hole diameter is precisely 13 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.

Pros as well as cons of Nd₂Fe₁₄B magnets.

Benefits

Apart from their notable power, neodymium magnets have these key benefits:

Their power is maintained, and after approximately 10 years it drops only by ~1% (according to research),
Magnets very well defend themselves against demagnetization caused by external fields,
A magnet with a smooth nickel surface looks better,
Magnetic induction on the working layer of the magnet remains very high,
Due to their durability and thermal resistance, neodymium magnets can operate (depending on the form) even at high temperatures reaching 230°C or more...
Considering the option of flexible shaping and customization to individualized requirements, NdFeB magnets can be manufactured in a wide range of geometric configurations, which expands the range of possible applications,
Significant place in electronics industry – they are used in HDD drives, drive modules, diagnostic systems, as well as modern systems.
Thanks to concentrated force, small magnets offer high operating force, occupying minimum space,

Weaknesses

Disadvantages of NdFeB magnets:

To avoid cracks under impact, we recommend using special steel housings. 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 durability even at temperatures up to 230°C
When exposed to humidity, magnets usually 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 casing - magnetic mount, due to difficulties in producing nuts inside the magnet and complicated shapes.
Potential hazard related to microscopic parts of magnets pose a threat, if swallowed, which becomes key in the context of child safety. Additionally, small elements of these magnets are able to complicate diagnosis medical when they are in the body.
With mass production the cost of neodymium magnets is a challenge,

Pull force analysis

Detachment force of the magnet in optimal conditions – what affects it?

The specified lifting capacity refers to the peak performance, recorded under laboratory conditions, namely:

on a block made of structural steel, perfectly concentrating the magnetic flux
with a cross-section no less than 10 mm
with an ideally smooth touching surface
without any insulating layer between the magnet and steel
during pulling in a direction perpendicular to the plane
at ambient temperature approx. 20 degrees Celsius

Lifting capacity in real conditions – factors

It is worth knowing that the application force will differ depending on the following factors, in order of importance:

Air gap (betwixt the magnet and the plate), because even a very small distance (e.g. 0.5 mm) results in a reduction in lifting capacity by up to 50% (this also applies to varnish, rust or dirt).
Force direction – note that the magnet has greatest strength perpendicularly. Under sliding down, the capacity drops drastically, often to levels of 20-30% of the nominal value.
Metal thickness – the thinner the sheet, the weaker the hold. Magnetic flux passes through the material instead of converting into lifting capacity.
Metal type – not every steel reacts the same. High carbon content worsen the interaction with the magnet.
Surface finish – ideal contact is obtained only on polished steel. Any scratches and bumps create air cushions, weakening the magnet.
Thermal environment – heating the magnet results in weakening of force. It is worth remembering the thermal limit for a given model.

Lifting capacity testing was conducted on a smooth plate of optimal thickness, under a perpendicular pulling force, in contrast under parallel forces the load capacity is reduced by as much as 75%. Additionally, even a slight gap between the magnet’s surface and the plate lowers the load capacity.

Safe handling of neodymium magnets

Danger to pacemakers

For implant holders: Strong magnetic fields affect medical devices. Keep at least 30 cm distance or request help to handle the magnets.

Heat warning

Keep cool. NdFeB magnets are sensitive to heat. If you require operation above 80°C, ask us about HT versions (H, SH, UH).

Protect data

Equipment safety: Neodymium magnets can damage data carriers and delicate electronics (heart implants, medical aids, mechanical watches).

Beware of splinters

Despite the nickel coating, neodymium is brittle and cannot withstand shocks. Avoid impacts, as the magnet may crumble into hazardous fragments.

Compass and GPS

Navigation devices and smartphones are extremely sensitive to magnetic fields. Direct contact with a strong magnet can decalibrate the internal compass in your phone.

Nickel allergy

Medical facts indicate that nickel (the usual finish) is a potent allergen. For allergy sufferers, refrain from direct skin contact and select versions in plastic housing.

Crushing risk

Pinching hazard: The pulling power is so great that it can cause hematomas, pinching, and even bone fractures. Protective gloves are recommended.

Safe operation

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

Fire risk

Mechanical processing of NdFeB material carries a risk of fire hazard. Neodymium dust reacts violently with oxygen and is hard to extinguish.

Adults only

Product intended for adults. Small elements can be swallowed, leading to intestinal necrosis. Keep out of reach of children and animals.

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

MP 25x13x4 / N38 - ring magnet

Technical specification of the product - MP 25x13x4 / N38 - ring magnet

Magnetic properties of material N38

Physical properties of sintered neodymium magnets Nd2Fe14B at 20°C

Engineering modeling of the product - technical parameters

Table 1: Static force (force vs distance) - interaction chart MP 25x13x4 / N38

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

Table 3: Wall mounting (sliding) - behavior on slippery surfaces MP 25x13x4 / N38

Table 4: Steel thickness (saturation) - power losses MP 25x13x4 / N38

Table 5: Thermal stability (material behavior) - thermal limit MP 25x13x4 / N38

Table 6: Two magnets (repulsion) - field collision MP 25x13x4 / N38

Table 7: Hazards (implants) - precautionary measures MP 25x13x4 / N38

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

Table 9: Anti-corrosion coating durability MP 25x13x4 / N38

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

Table 11: Underwater work (magnet fishing) MP 25x13x4 / N38

1. Wall mount (shear)

2. Efficiency vs thickness

3. Thermal stability

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

Material specification

Ecology and recycling (GPSR)

Magnet pull force

Magnetic Induction

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Pros as well as cons of Nd2Fe14B magnets.

Benefits

Weaknesses

Pull force analysis

Detachment force of the magnet in optimal conditions – what affects it?

Lifting capacity in real conditions – factors

Safe handling of neodymium magnets

Danger to pacemakers

Heat warning

Protect data

Beware of splinters

Compass and GPS

Nickel allergy

Crushing risk

Safe operation

Fire risk

Adults only

Physical properties of sintered neodymium magnets Nd₂Fe₁₄B at 20°C

Table 1: Static force (force vs distance) - interaction chart
MP 25x13x4 / N38

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

Table 3: Wall mounting (sliding) - behavior on slippery surfaces
MP 25x13x4 / N38

Table 4: Steel thickness (saturation) - power losses
MP 25x13x4 / N38

Table 5: Thermal stability (material behavior) - thermal limit
MP 25x13x4 / N38

Table 6: Two magnets (repulsion) - field collision
MP 25x13x4 / N38

Table 7: Hazards (implants) - precautionary measures
MP 25x13x4 / N38

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

Table 9: Anti-corrosion coating durability
MP 25x13x4 / N38

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

Table 11: Underwater work (magnet fishing)
MP 25x13x4 / N38

Pros as well as cons of Nd₂Fe₁₄B magnets.