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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 specifications »

6.77 ZŁ with VAT / pcs + price for transport

5.50 ZŁ net + 23% VAT / pcs

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Physical properties - 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 simulation of the assembly - technical parameters

The following data represent the direct effect of a mathematical calculation. Values were calculated on algorithms for the material Nd₂Fe₁₄B. Actual conditions might slightly differ from theoretical values. Treat these data as a supplementary guide for designers.

Table 1: Static force (pull 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 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	low risk
10 mm	2073 Gs 207.3 mT	0.53 kg / 1.17 LBS 532.9 g / 5.2 N	low risk
15 mm	1231 Gs 123.1 mT	0.19 kg / 0.41 LBS 188.0 g / 1.8 N	low risk
20 mm	773 Gs 77.3 mT	0.07 kg / 0.16 LBS 74.0 g / 0.7 N	low risk
30 mm	356 Gs 35.6 mT	0.02 kg / 0.03 LBS 15.7 g / 0.2 N	low risk
50 mm	115 Gs 11.5 mT	0.00 kg / 0.00 LBS 1.6 g / 0.0 N	low risk

Grip strength drops sharply per each millimeter of spacing. Note that every additional insulation layer (e.g., contamination, paint, veneer) strongly weakens the grip. Magnets work strongest during direct contact; distance weakens the force. Notice how quickly the pull force fall, when the product does not touch tightly to the steel surface. When planning the arrangement, avoid unnecessary gaps.

Table 2: Vertical hold (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 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 presents the approximate weight limit required to cause the downward movement of the magnet downwards against a vertical metal surface (considering standard friction coefficient). The holding force depends on the distance between the magnet and the surface.

Table 3: Wall mounting (shearing) - vertical pull
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 hanging a element on a vertical plane (e.g., a board), it you can count on just about 1/5 of nominal attraction strength. Gravitational force as well as a low friction coefficient cause that holders slip easier than they detach. Designing a hanger? Consider that the sliding force is noticeably lower than the perpendicular breakaway force. On a painted metal, the magnet will slip down under a significantly smaller cargo. Using a rubber coating can drastically improve the result.

Table 4: Material efficiency (substrate influence) - 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 thin metal plate cannot take in the full magnetic flux, which squanders power of the magnet. Should you install a neodymium to a weak sheet, the magnetism will penetrate right through and the holding will be smaller. To achieve full efficiency of this magnet's potential, you need a suitably thick element of metal. The saturation effect causes that on delicate walls (e.g., appliance housings), the holder shows lower pull force. We advise picking the steel cross-section according to the table below.

Table 5: Working in heat (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

Standard neodymium magnets change their properties power after exceeding the maximum temperature. Avoid high temperatures – heat can permanently destroy this product. As the temperature rises, the magnet's power briefly lowers. Avoid using this product close to ovens higher than its operating temperature limit. Exceeding the critical threshold will result in irreversible degradation of magnetic properties.

*Technical advisory: Thermal stability is determined by both grade, as well as the dimension ratios. Low-profile magnets (pancake types) may lose charge permanently at lower temperatures than taller cylinders. Red status in the table signals permanent field degradation for this particular item.

Table 6: Two magnets (attraction) - field range
MP 25x13x4 / N38

Gap (mm)	Attraction (kg/lbs) (N-S)	Shear Force (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 magnets attract each other from a significantly greater distance than a magnet and sheet setup. The connection of two magnets produces a massive flux and a larger range of action. Planning to create a solid fastener? Apply two magnets instead of a neodymium and a striker plate. Exercise caution that when bringing together two magnets, the pinch force is massive. The levitation is a bit weaker than the attraction, but still impressive.
*Field value for N-N configuration drops to ~0 Gs in the exact middle between the magnets (caused by magnetic field nullification).
Note: Estimates refer to shear force of dual same neodymium magnets (friction coefficient ~0.15 for Ni-Ni plating).

Table 7: Safety (HSE) (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 is a serious hazard to IT equipment as well as pacemakers. These NdFeB products generate a flux that disrupts operation of digital equipment. Remember: the unseen radiation penetrates the body and plastic. Special caution must be taken by people with cochlear implants and insulin pumps. Influence will be felt by: mechanical watches, remotes, membranes, and screens. Do not bring the product near payment cards, HDD media, or sensitive navigation tools.

Table 8: Impact energy (cracking risk) - collision effects
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 delicate – a strong collision with metal risks their cracking. Pay attention to connection velocity – a neodymium left loose turns into a projectile. Impact energy can destroy the magnet or painful pinches to fingers. Always hold the magnet 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 safety glasses when handling with powerful specimens.

Table 9: Coating parameters (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: Construction 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)

Flux value passing through the pole surface. Essential parameter for generator designers as well as sensors. The P_c coefficient determines the working geometry.

Table 11: Hydrostatics and buoyancy
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%

Corrosion warning: 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. Sliding resistance

*Warning: On a vertical wall, the magnet holds merely approx. 20-30% of its nominal pull.

2. Steel thickness impact

*Thin metal sheet (e.g. computer case) drastically reduces the holding force.

3. Power loss vs temp

*For N38 material, the critical limit is 80°C.

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

chart generated for the permeance coefficient P_c (Permeance Coefficient) = 1.02

This simulation demonstrates the magnetic stability of the selected magnet under specific geometric conditions. 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

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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It is ideally suited for places where solid attachment of the magnet to the substrate is required without the risk of detachment. Thanks to the hole (often for a screw), this model enables quick installation to wood, wall, plastic, or metal. This product with a force of 4.14 kg works great as a door latch, speaker holder, or mounting 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.

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.

A screw or bolt with a thread diameter smaller than 13 mm fits this model. If the magnet does not have a chamfer (cone), we recommend using a screw with a flat or cylindrical head, or possibly using a washer. Aesthetic mounting requires selecting the appropriate head size.

This model is characterized by dimensions Ø25x4 mm and a weight of 10.74 g. The pulling force of this model is an impressive 4.14 kg, which translates to 40.57 N in newtons. The product has a [NiCuNi] coating and is made of NdFeB material. Inner hole dimension: 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.

Strengths and weaknesses of neodymium magnets.

Advantages

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

They retain attractive force for around ten years – the loss is just ~1% (in theory),
They have excellent resistance to magnetism drop due to opposing magnetic fields,
By covering with a lustrous layer of silver, the element gains an nice look,
They show high magnetic induction at the operating surface, which increases their power,
Due to their durability and thermal resistance, neodymium magnets are capable of operate (depending on the form) even at high temperatures reaching 230°C or more...
Possibility of individual modeling as well as adjusting to precise applications,
Versatile presence in high-tech industry – they are utilized in magnetic memories, drive modules, precision medical tools, and modern systems.
Thanks to efficiency per cm³, small magnets offer high operating force, in miniature format,

Limitations

What to avoid - cons of neodymium magnets: weaknesses and usage proposals

To avoid cracks upon strong impacts, we recommend using special steel holders. Such a solution protects the magnet and simultaneously improves its durability.
We warn that neodymium magnets can lose their strength at high temperatures. To prevent this, we suggest 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 magnets in rubber or plastics, which prevent oxidation and corrosion.
Limited ability of producing threads in the magnet and complicated forms - recommended is cover - magnet mounting.
Possible danger to health – tiny shards of magnets pose a threat, in case of ingestion, which gains importance in the context of child safety. It is also worth noting that small elements of these magnets are able to be problematic in diagnostics medical when they are in the body.
High unit price – neodymium magnets cost more than other types of magnets (e.g. ferrite), which can limit application in large quantities

Pull force analysis

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

Breakaway force was determined for ideal contact conditions, assuming:

with the application of a sheet made of special test steel, guaranteeing full magnetic saturation
possessing a massiveness of minimum 10 mm to ensure full flux closure
with an polished contact surface
without any insulating layer between the magnet and steel
during detachment in a direction perpendicular to the plane
in neutral thermal conditions

Determinants of practical lifting force of a magnet

Bear in mind that the working load will differ subject to elements below, in order of importance:

Space between surfaces – even a fraction of a millimeter of distance (caused e.g. by varnish or dirt) diminishes the magnet efficiency, often by half at just 0.5 mm.
Force direction – note that the magnet holds strongest perpendicularly. Under shear forces, the holding force drops drastically, often to levels of 20-30% of the maximum value.
Steel thickness – too thin plate causes magnetic saturation, causing part of the power to be escaped to the other side.
Steel type – mild steel gives the best results. Alloy admixtures reduce magnetic permeability and lifting capacity.
Base smoothness – the more even the surface, the better the adhesion and stronger the hold. Unevenness acts like micro-gaps.
Heat – NdFeB sinters have a sensitivity to temperature. At higher temperatures they are weaker, and in frost they can be stronger (up to a certain limit).

Lifting capacity was measured using a smooth steel plate of optimal thickness (min. 20 mm), under vertically applied force, in contrast under shearing force the load capacity is reduced by as much as 75%. Moreover, even a minimal clearance between the magnet and the plate lowers the lifting capacity.

H&S for magnets

Skin irritation risks

Warning for allergy sufferers: The Ni-Cu-Ni coating contains nickel. If skin irritation happens, immediately stop working with magnets and use protective gear.

Magnetic interference

A powerful magnetic field interferes with the functioning of magnetometers in phones and navigation systems. Do not bring magnets near a smartphone to prevent damaging the sensors.

Safe distance

Avoid bringing magnets close to a purse, computer, or screen. The magnetism can destroy these devices and wipe information from cards.

Thermal limits

Monitor thermal conditions. Exposing the magnet above 80 degrees Celsius will destroy its properties and pulling force.

This is not a toy

These products are not intended for children. Accidental ingestion of multiple magnets may result in them attracting across intestines, which poses a severe health hazard and necessitates immediate surgery.

Pacemakers

Individuals with a heart stimulator have to maintain an safe separation from magnets. The magnetic field can stop the operation of the implant.

Magnet fragility

Despite the nickel coating, the material is brittle and not impact-resistant. Avoid impacts, as the magnet may shatter into hazardous fragments.

Bone fractures

Big blocks can smash fingers instantly. Under no circumstances place your hand betwixt two attracting surfaces.

Fire risk

Dust created during grinding of magnets is combustible. Do not drill into magnets unless you are an expert.

Powerful field

Exercise caution. Neodymium magnets act from a long distance and connect with huge force, often quicker than you can move away.

Warning! Looking for details? Read our article: Are neodymium magnets dangerous?

MP 25x13x4 / N38 - ring magnet

Physical properties - MP 25x13x4 / N38 - ring magnet

Magnetic properties of material N38

Physical properties of sintered neodymium magnets Nd2Fe14B at 20°C

Engineering simulation of the assembly - technical parameters

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

Table 2: Vertical hold (vertical surface) MP 25x13x4 / N38

Table 3: Wall mounting (shearing) - vertical pull MP 25x13x4 / N38

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

Table 5: Working in heat (material behavior) - resistance threshold MP 25x13x4 / N38

Table 6: Two magnets (attraction) - field range MP 25x13x4 / N38

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

Table 8: Impact energy (cracking risk) - collision effects MP 25x13x4 / N38

Table 9: Coating parameters (durability) MP 25x13x4 / N38

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

Table 11: Hydrostatics and buoyancy MP 25x13x4 / N38

1. Sliding resistance

2. Steel thickness impact

3. Power loss vs temp

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

Chemical composition

Ecology and recycling (GPSR)

Pulling force

Field Strength

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Strengths and weaknesses of neodymium magnets.

Advantages

Limitations

Pull force analysis

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

Determinants of practical lifting force of a magnet

H&S for magnets

Skin irritation risks

Magnetic interference

Safe distance

Thermal limits

This is not a toy

Pacemakers

Magnet fragility

Bone fractures

Fire risk

Powerful field

Physical properties of sintered neodymium magnets Nd₂Fe₁₄B at 20°C

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

Table 2: Vertical hold (vertical surface)
MP 25x13x4 / N38

Table 3: Wall mounting (shearing) - vertical pull
MP 25x13x4 / N38

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

Table 5: Working in heat (material behavior) - resistance threshold
MP 25x13x4 / N38

Table 6: Two magnets (attraction) - field range
MP 25x13x4 / N38

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

Table 8: Impact energy (cracking risk) - collision effects
MP 25x13x4 / N38

Table 9: Coating parameters (durability)
MP 25x13x4 / N38

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

Table 11: Hydrostatics and buoyancy
MP 25x13x4 / N38