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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

technical parameters »

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Product card - 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

Technical simulation of the assembly - data

Presented values are the direct effect of a mathematical analysis. Values are based on algorithms for the class Nd₂Fe₁₄B. Real-world parameters might slightly differ. Treat these calculations as a preliminary roadmap for designers.

Table 1: Static force (force vs distance) - power drop
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 LBS 4140.0 g / 40.6 N	medium risk
1 mm	5310 Gs 531.0 mT	3.50 kg / 7.71 LBS 3497.4 g / 34.3 N	medium risk
2 mm	4846 Gs 484.6 mT	2.91 kg / 6.42 LBS 2912.4 g / 28.6 N	medium risk
3 mm	4397 Gs 439.7 mT	2.40 kg / 5.29 LBS 2398.5 g / 23.5 N	medium risk
5 mm	3576 Gs 357.6 mT	1.59 kg / 3.50 LBS 1586.2 g / 15.6 N	weak grip
10 mm	2073 Gs 207.3 mT	0.53 kg / 1.17 LBS 532.9 g / 5.2 N	weak grip
15 mm	1231 Gs 123.1 mT	0.19 kg / 0.41 LBS 188.0 g / 1.8 N	weak grip
20 mm	773 Gs 77.3 mT	0.07 kg / 0.16 LBS 74.0 g / 0.7 N	weak grip
30 mm	356 Gs 35.6 mT	0.02 kg / 0.03 LBS 15.7 g / 0.2 N	weak grip
50 mm	115 Gs 11.5 mT	0.00 kg / 0.00 LBS 1.6 g / 0.0 N	weak grip

Pulling power weakens significantly with every mm of distance. Note that even the smallest gap (e.g., dirt, paint, rust) significantly weakens the grip. Neodymiums work strongest during direct contact; gap weakens the power. Analyze how rapidly the pull force plummet, when the product does not adhere flatly to the steel surface. When calculating the arrangement, avoid additional spacers.

Table 2: Vertical capacity (wall)
MP 25x13x4 / N38

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

This section defines the approximate force needed to initiate the downward movement of the magnet vertically along a vertical metal surface (assuming typical friction). This value is relative to the separation distance 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 LBS 1242.0 g / 12.2 N
Painted steel (standard)	µ = 0.2 20% Nominalnej Siły	0.83 kg / 1.83 LBS 828.0 g / 8.1 N
Oily/slippery steel	µ = 0.1 10% Nominalnej Siły	0.41 kg / 0.91 LBS 414.0 g / 4.1 N
Magnet with anti-slip rubber	µ = 0.5 50% Nominalnej Siły	2.07 kg / 4.56 LBS 2070.0 g / 20.3 N

When mounting a element on a vertical wall (e.g., a car body), it you can count on barely approx. 20%-30% of its nominal power. Gravity and a weak degree of grip influence the fact that products slip 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 smooth steel, the holder will slide down under a noticeably lighter cargo. Utilizing a rubberized pad can effectively increase the grip.

Table 4: Material efficiency (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 LBS 414.0 g / 4.1 N
1 mm	25%	1.04 kg / 2.28 LBS 1035.0 g / 10.2 N
2 mm	50%	2.07 kg / 4.56 LBS 2070.0 g / 20.3 N
3 mm	75%	3.10 kg / 6.85 LBS 3105.0 g / 30.5 N
5 mm	100%	4.14 kg / 9.13 LBS 4140.0 g / 40.6 N
10 mm	100%	4.14 kg / 9.13 LBS 4140.0 g / 40.6 N
11 mm	100%	4.14 kg / 9.13 LBS 4140.0 g / 40.6 N
12 mm	100%	4.14 kg / 9.13 LBS 4140.0 g / 40.6 N

A too thin steel is not enough to take in the entire magnetic field, which wastes potential of the holder. If you install a neodymium to a thin surface, the field will pass right through and the attraction force will be weaker. To utilize 100% of this neodymium's power, you need a suitably thick piece of steel. The saturation phenomenon means that on delicate walls (e.g., appliance housings), the product holds weaker. We advise picking the steel dimension according to the table below.

Table 5: Thermal resistance (material behavior) - resistance threshold
MP 25x13x4 / N38

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

Classic neodymiums irreversibly lose parameters above the temperature limit. Watch out for overheating – high temperature can permanently destroy this magnet. With increasing heat, the neodymium's power temporarily lowers. Do not use this magnet in hot environments higher than its operating temperature limit. Ignoring the limit will cause destruction of magnetism.

*Important note: Heat tolerance depends not only on the material grade, but also on the magnet's shape. Thin magnets (low permeance coefficient) are more susceptible to demagnetization sooner compared to rod magnets. Warning indicator in the table indicates a risk of irreversible loss for this specific geometry.

Table 6: Magnet-Magnet interaction (repulsion) - field range
MP 25x13x4 / N38

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

Two magnetic products interact from a much further distance than a magnet and sheet combination. Such a system of two magnets creates a more powerful interaction and a wider radius of performance. Want to build a solid fastener? Use a pair of magnets instead of one magnet and a steel. Remember that when bringing together two magnets, the pinch force is extreme. The repulsion force is slightly lower than the connection force, but still impressive.
*Flux density for N-N configuration reaches ~0 Gs in the exact middle between the magnets (due to field cancellation).
* Figures apply to shear force of dual matching magnets (friction ~0.15 for Ni-Ni layer).

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
Timepiece	20 Gs (2.0 mT)	10.5 cm
Mobile device	40 Gs (4.0 mT)	8.0 cm
Remote	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 poses a large risk to electronics and medical implants. These neodymiums produce a field that prevents correct functioning of sensitive medical devices. Be aware: the invisible magnetic field acts through matter and plastic. Special caution must be taken by people with cochlear implants and drug dispensers. Influence will be felt by: automatic timepieces, remotes, speakers, and displays. Do not bring the product near payment cards, hard drives, or precise measuring instruments.

Table 8: Impact energy (kinetic energy) - 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

Neodymium magnets are prone to chipping – a violent impact against metal can result in shattering. Watch the impact speed – a magnet released freely speeds with massive force. Striking energy can cause material chips or dangerous crushing to skin. Be sure to control the product during bringing near metal so it doesn't slam with momentum against the steel surface. A contact at a velocity of dozens of km/h means shattering of the magnet. Wear eye protection 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. Note the thickness of the protective layer.

Table 10: Electrical data (P_c)
MP 25x13x4 / N38

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

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

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

Contrary to myths, water does not block the magnetic field. However, remember the water resistance when pulling the rope quickly.

1. Shear force

*Note: On a vertical wall, the magnet holds merely a fraction of its nominal pull.

2. Efficiency vs thickness

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

3. Power loss vs temp

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

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

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

Technical and environmental data

Chemical composition

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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MP 16x12x2 / N38 - ring magnet

1.304 ZŁ brutto / pcs

The ring-shaped magnet 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 cabinet closure, 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. 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 flexible washer under the screw head, which will cushion the stresses. Remember: cracking during assembly results from material properties, not a product defect.

Moisture can penetrate micro-cracks in the coating and cause oxidation of the magnet. Damage to the protective layer during assembly is the most common cause of rusting. This product is dedicated for indoor use. For outdoor applications, we recommend choosing magnets in hermetic housing 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. Aesthetic mounting requires selecting the appropriate head size.

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 product has a [NiCuNi] coating and is made of NdFeB material. Inner hole dimension: 13 mm.

These magnets are magnetized axially (through the thickness), which means one flat side is the N pole and the other is S. If you want two such magnets screwed with cones facing each other (faces) to attract, you must connect them with opposite poles (N to S). 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.

Benefits

Besides their magnetic performance, neodymium magnets are valued for these benefits:

They retain full power for almost 10 years – the loss is just ~1% (according to analyses),
They have excellent resistance to weakening of magnetic properties as a result of external magnetic sources,
The use of an metallic finish of noble metals (nickel, gold, silver) causes the element to present itself better,
Magnetic induction on the working part of the magnet is extremely intense,
Thanks to resistance to high temperature, they are able to function (depending on the form) even at temperatures up to 230°C and higher...
Thanks to versatility in forming and the capacity to customize to individual projects,
Wide application in innovative solutions – they are utilized in mass storage devices, electromotive mechanisms, precision medical tools, and complex engineering applications.
Relatively small size with high pulling force – neodymium magnets offer impressive pulling force in tiny dimensions, which allows their use in miniature devices

Disadvantages

Disadvantages of NdFeB magnets:

Brittleness is one of their disadvantages. Upon intense impact they can break. We advise keeping them in a steel housing, which not only protects them against impacts but also raises their durability
We warn that neodymium magnets can lose their power at high temperatures. To prevent this, we suggest our specialized [AH] magnets, which work effectively even at 230°C.
They oxidize in a humid environment - during use outdoors we suggest using waterproof magnets e.g. in rubber, plastic
Due to limitations in realizing threads and complex shapes in magnets, we propose using cover - magnetic holder.
Possible danger related to microscopic parts of magnets are risky, in case of ingestion, which is particularly important in the aspect of protecting the youngest. Additionally, small elements of these devices can be problematic in diagnostics medical after entering the body.
Due to expensive raw materials, their price is relatively high,

Pull force analysis

Magnetic strength at its maximum – what affects it?

The load parameter shown represents the peak performance, measured under laboratory conditions, meaning:

using a sheet made of low-carbon steel, functioning as a magnetic yoke
with a thickness no less than 10 mm
with a plane cleaned and smooth
under conditions of no distance (surface-to-surface)
under perpendicular force vector (90-degree angle)
at room temperature

Key elements affecting lifting force

During everyday use, the actual holding force is determined by a number of factors, presented from crucial:

Clearance – the presence of any layer (rust, dirt, air) interrupts the magnetic circuit, which lowers capacity steeply (even by 50% at 0.5 mm).
Force direction – declared lifting capacity refers to pulling vertically. When attempting to slide, the magnet holds significantly lower power (typically approx. 20-30% of nominal force).
Element thickness – for full efficiency, the steel must be adequately massive. Thin sheet limits the attraction force (the magnet "punches through" it).
Metal type – not every steel attracts identically. High carbon content worsen the interaction with the magnet.
Plate texture – ground elements ensure maximum contact, which increases field saturation. Uneven metal weaken the grip.
Thermal conditions – NdFeB sinters have a sensitivity to temperature. When it is hot they lose power, and at low temperatures they can be stronger (up to a certain limit).

Holding force was tested on a smooth steel plate of 20 mm thickness, when a perpendicular force was applied, in contrast under shearing force the lifting capacity is smaller. Additionally, even a minimal clearance between the magnet and the plate lowers the load capacity.

Safe handling of neodymium magnets

Demagnetization risk

Do not overheat. NdFeB magnets are sensitive to heat. If you need operation above 80°C, look for special high-temperature series (H, SH, UH).

Medical interference

Individuals with a ICD have to maintain an large gap from magnets. The magnetism can interfere with the operation of the life-saving device.

Flammability

Combustion risk: Neodymium dust is explosive. Do not process magnets in home conditions as this risks ignition.

No play value

Always keep magnets out of reach of children. Risk of swallowing is significant, and the effects of magnets clamping inside the body are tragic.

Avoid contact if allergic

Warning for allergy sufferers: The nickel-copper-nickel coating contains nickel. If redness occurs, immediately stop handling magnets and wear gloves.

Safe distance

Data protection: Neodymium magnets can ruin data carriers and delicate electronics (heart implants, medical aids, timepieces).

Serious injuries

Large magnets can smash fingers in a fraction of a second. Do not put your hand betwixt two strong magnets.

Handling guide

Before starting, read the rules. Sudden snapping can destroy the magnet or injure your hand. Think ahead.

Eye protection

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

Keep away from electronics

A powerful magnetic field negatively affects the operation of magnetometers in smartphones and navigation systems. Maintain magnets near a smartphone to prevent damaging the sensors.

Danger! More info about risks in the article: Magnet Safety Guide.

MP 25x13x4 / N38 - ring magnet

Product card - MP 25x13x4 / N38 - ring magnet

Magnetic properties of material N38

Physical properties of sintered neodymium magnets Nd2Fe14B at 20°C

Technical simulation of the assembly - data

Table 1: Static force (force vs distance) - power drop MP 25x13x4 / N38

Table 2: Vertical capacity (wall) MP 25x13x4 / N38

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

Table 4: Material efficiency (saturation) - power losses MP 25x13x4 / N38

Table 5: Thermal resistance (material behavior) - resistance threshold MP 25x13x4 / N38

Table 6: Magnet-Magnet interaction (repulsion) - field range MP 25x13x4 / N38

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

Table 8: Impact energy (kinetic energy) - warning MP 25x13x4 / N38

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

Table 10: Electrical data (Pc) MP 25x13x4 / N38

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

1. Shear force

2. Efficiency vs thickness

3. Power loss vs temp

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

Chemical composition

Ecology and recycling (GPSR)

Force (pull)

Magnetic Field

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Advantages as well as disadvantages of Nd2Fe14B magnets.

Benefits

Disadvantages

Pull force analysis

Magnetic strength at its maximum – what affects it?

Key elements affecting lifting force

Safe handling of neodymium magnets

Demagnetization risk

Medical interference

Flammability

No play value

Avoid contact if allergic

Safe distance

Serious injuries

Handling guide

Eye protection

Keep away from electronics

Physical properties of sintered neodymium magnets Nd₂Fe₁₄B at 20°C

Table 1: Static force (force vs distance) - power drop
MP 25x13x4 / N38

Table 2: Vertical capacity (wall)
MP 25x13x4 / N38

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

Table 4: Material efficiency (saturation) - power losses
MP 25x13x4 / N38

Table 5: Thermal resistance (material behavior) - resistance threshold
MP 25x13x4 / N38

Table 6: Magnet-Magnet interaction (repulsion) - field range
MP 25x13x4 / N38

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

Table 8: Impact energy (kinetic energy) - warning
MP 25x13x4 / N38

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

Table 10: Electrical data (P_c)
MP 25x13x4 / N38

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

Advantages as well as disadvantages of Nd₂Fe₁₄B magnets.