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MP 25x7.5/4.5x5 / 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 030194

GTIN/EAN: 5906301812111

5.00

Diameter

25 mm [±0,1 mm]

internal diameter Ø

7.5/4.5 mm [±0,1 mm]

Height

5 mm [±0,1 mm]

Weight

17.81 g

Magnetization Direction

↑ axial

Load capacity

7.72 kg / 75.69 N

Magnetic Induction

230.20 mT / 2302 Gs

Coating

[NiCuNi] Nickel

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Specifications along with form of a neodymium magnet can be tested with our modular calculator.

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Technical data of the product - MP 25x7.5/4.5x5 / N38 - ring magnet

Specification / characteristics - MP 25x7.5/4.5x5 / N38 - ring magnet

properties

properties	values
Cat. no.	030194
GTIN/EAN	5906301812111
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	7.5/4.5 mm [±0,1 mm]
Height	5 mm [±0,1 mm]
Weight	17.81 g
Magnetization Direction	↑ axial
Load capacity ~ ?	7.72 kg / 75.69 N
Magnetic Induction ~ ?	230.20 mT / 2302 Gs
Coating	[NiCuNi] Nickel
Manufacturing Tolerance	±0.1 mm

Magnetic properties of material N38

Specification / characteristics MP 25x7.5/4.5x5 / N38 - ring magnet

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

Physical properties of sintered neodymium magnets Nd₂Fe₁₄B at 20°C

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

Engineering analysis of the magnet - data

The following values represent the result of a physical calculation. Results rely on models for the material Nd₂Fe₁₄B. Actual conditions may differ from theoretical values. Please consider these calculations as a supplementary guide for designers.

Table 1: Static force (pull vs distance) - characteristics
MP 25x7.5/4.5x5 / N38

Distance (mm)	Induction (Gauss) / mT	Pull Force (kg/lbs/g/N)	Risk Status
0 mm	1995 Gs 199.5 mT	7.72 kg / 17.02 LBS 7720.0 g / 75.7 N	strong
1 mm	1906 Gs 190.6 mT	7.05 kg / 15.54 LBS 7049.4 g / 69.2 N	strong
2 mm	1793 Gs 179.3 mT	6.24 kg / 13.75 LBS 6236.8 g / 61.2 N	strong
3 mm	1664 Gs 166.4 mT	5.37 kg / 11.84 LBS 5368.9 g / 52.7 N	strong
5 mm	1385 Gs 138.5 mT	3.72 kg / 8.21 LBS 3722.8 g / 36.5 N	strong
10 mm	788 Gs 78.8 mT	1.20 kg / 2.65 LBS 1203.8 g / 11.8 N	safe
15 mm	437 Gs 43.7 mT	0.37 kg / 0.82 LBS 370.3 g / 3.6 N	safe
20 mm	253 Gs 25.3 mT	0.12 kg / 0.27 LBS 124.5 g / 1.2 N	safe
30 mm	101 Gs 10.1 mT	0.02 kg / 0.04 LBS 19.8 g / 0.2 N	safe
50 mm	27 Gs 2.7 mT	0.00 kg / 0.00 LBS 1.4 g / 0.0 N	safe

Pulling power decreases significantly per each millimeter of distance. Remember that even a very thin break (e.g., contamination, varnish, dust) significantly weakens the grip. Magnetic products hold most effectively at the point of direct contact; distance drastically cuts the power. Analyze how rapidly the pull force plummet, when the product does not touch flatly to the steel surface. When planning the assembly, avoid redundant distances.

Table 2: Slippage capacity (vertical surface)
MP 25x7.5/4.5x5 / N38

Distance (mm)	Friction coefficient	Pull Force (kg/lbs/g/N)
0 mm	Stal (~0.2)	1.54 kg / 3.40 LBS 1544.0 g / 15.1 N
1 mm	Stal (~0.2)	1.41 kg / 3.11 LBS 1410.0 g / 13.8 N
2 mm	Stal (~0.2)	1.25 kg / 2.75 LBS 1248.0 g / 12.2 N
3 mm	Stal (~0.2)	1.07 kg / 2.37 LBS 1074.0 g / 10.5 N
5 mm	Stal (~0.2)	0.74 kg / 1.64 LBS 744.0 g / 7.3 N
10 mm	Stal (~0.2)	0.24 kg / 0.53 LBS 240.0 g / 2.4 N
15 mm	Stal (~0.2)	0.07 kg / 0.16 LBS 74.0 g / 0.7 N
20 mm	Stal (~0.2)	0.02 kg / 0.05 LBS 24.0 g / 0.2 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

The table below shows the estimated weight limit sufficient to initiate the slippage of the magnet down on a vertical steel plate (assuming typical friction). This value varies with the distance between the magnet and the surface.

Table 3: Wall mounting (shearing) - behavior on slippery surfaces
MP 25x7.5/4.5x5 / N38

Surface type	Friction coefficient / % Mocy	Max load (kg/lbs/g/N)
Raw steel	µ = 0.3 30% Nominalnej Siły	2.32 kg / 5.11 LBS 2316.0 g / 22.7 N
Painted steel (standard)	µ = 0.2 20% Nominalnej Siły	1.54 kg / 3.40 LBS 1544.0 g / 15.1 N
Oily/slippery steel	µ = 0.1 10% Nominalnej Siły	0.77 kg / 1.70 LBS 772.0 g / 7.6 N
Magnet with anti-slip rubber	µ = 0.5 50% Nominalnej Siły	3.86 kg / 8.51 LBS 3860.0 g / 37.9 N

When placing a element on a upright wall (e.g., a fridge), it will maintain barely about 1/5 of nominal attraction strength. Gravitational force and a low friction coefficient mean that holders slide down faster than they pop off the substrate. Planning a hanger? Remember that the shear force is significantly lower than the perpendicular breakaway force. On a slippery surface, the element will give way down under a significantly smaller weight. Application of an anti-slip layer can effectively increase the grip.

Table 4: Material efficiency (saturation) - sheet metal selection
MP 25x7.5/4.5x5 / N38

Steel thickness (mm)	% power	Real pull force (kg/lbs/g/N)
0.5 mm	10%	0.77 kg / 1.70 LBS 772.0 g / 7.6 N
1 mm	25%	1.93 kg / 4.25 LBS 1930.0 g / 18.9 N
2 mm	50%	3.86 kg / 8.51 LBS 3860.0 g / 37.9 N
3 mm	75%	5.79 kg / 12.76 LBS 5790.0 g / 56.8 N
5 mm	100%	7.72 kg / 17.02 LBS 7720.0 g / 75.7 N
10 mm	100%	7.72 kg / 17.02 LBS 7720.0 g / 75.7 N
11 mm	100%	7.72 kg / 17.02 LBS 7720.0 g / 75.7 N
12 mm	100%	7.72 kg / 17.02 LBS 7720.0 g / 75.7 N

A thin metal plate is incapable of focus the full magnetic flux, which weakens actual performance of the holder. Should you mount a strong magnet to a weak sheet, the flux will penetrate right through and the attraction force will be weaker. To utilize the maximum of this neodymium's power, you require a sufficiently solid piece of metal. The saturation effect causes that on delicate walls (e.g., thin profiles), the magnet holds weaker. We suggest choosing the steel dimension based on the following data.

Table 5: Thermal stability (material behavior) - thermal limit
MP 25x7.5/4.5x5 / N38

Ambient temp. (°C)	Power loss	Remaining pull (kg/lbs/g/N)	Status
20 °C	0.0%	7.72 kg / 17.02 LBS 7720.0 g / 75.7 N	OK
40 °C	-2.2%	7.55 kg / 16.65 LBS 7550.2 g / 74.1 N	OK
60 °C	-4.4%	7.38 kg / 16.27 LBS 7380.3 g / 72.4 N
80 °C	-6.6%	7.21 kg / 15.90 LBS 7210.5 g / 70.7 N
100 °C	-28.8%	5.50 kg / 12.12 LBS 5496.6 g / 53.9 N

Ordinary NdFeB products change their properties parameters past the thermal threshold. Avoid high temperatures – high temperature can irreversibly destroy this product. With increasing heat, the magnet's capacity briefly lowers. Do not use this magnet close to heaters higher than its safe range. Too high temperature will result in permanent loss of magnetism.

*Technical advisory: Thermal stability depends not only on the material grade, but also on the magnet's shape. Flat magnets (low Pc) are more susceptible to demagnetization at lower temperatures compared to rod magnets. Red status in the table indicates permanent field degradation for this particular item.

Table 6: Magnet-Magnet interaction (repulsion) - forces in the system
MP 25x7.5/4.5x5 / N38

Gap (mm)	Attraction (kg/lbs) (N-S)	Shear Force (kg/lbs/g/N)	Repulsion (kg/lbs) (N-N)
0 mm	9.91 kg / 21.84 LBS 3 484 Gs	1.49 kg / 3.28 LBS 1486 g / 14.6 N	N/A
1 mm	9.51 kg / 20.96 LBS 3 909 Gs	1.43 kg / 3.14 LBS 1426 g / 14.0 N	8.56 kg / 18.87 LBS ~0 Gs
2 mm	9.05 kg / 19.94 LBS 3 813 Gs	1.36 kg / 2.99 LBS 1357 g / 13.3 N	8.14 kg / 17.95 LBS ~0 Gs
3 mm	8.54 kg / 18.83 LBS 3 705 Gs	1.28 kg / 2.82 LBS 1281 g / 12.6 N	7.69 kg / 16.94 LBS ~0 Gs
5 mm	7.45 kg / 16.42 LBS 3 460 Gs	1.12 kg / 2.46 LBS 1117 g / 11.0 N	6.70 kg / 14.78 LBS ~0 Gs
10 mm	4.78 kg / 10.53 LBS 2 771 Gs	0.72 kg / 1.58 LBS 717 g / 7.0 N	4.30 kg / 9.48 LBS ~0 Gs
20 mm	1.54 kg / 3.41 LBS 1 576 Gs	0.23 kg / 0.51 LBS 232 g / 2.3 N	1.39 kg / 3.06 LBS ~0 Gs
50 mm	0.06 kg / 0.13 LBS 312 Gs	0.01 kg / 0.02 LBS 9 g / 0.1 N	0.05 kg / 0.12 LBS ~0 Gs
60 mm	0.03 kg / 0.06 LBS 202 Gs	0.00 kg / 0.01 LBS 4 g / 0.0 N	0.02 kg / 0.05 LBS ~0 Gs
70 mm	0.01 kg / 0.03 LBS 138 Gs	0.00 kg / 0.00 LBS 2 g / 0.0 N	0.01 kg / 0.02 LBS ~0 Gs
80 mm	0.01 kg / 0.01 LBS 97 Gs	0.00 kg / 0.00 LBS 1 g / 0.0 N	0.00 kg / 0.00 LBS ~0 Gs
90 mm	0.00 kg / 0.01 LBS 71 Gs	0.00 kg / 0.00 LBS 0 g / 0.0 N	0.00 kg / 0.00 LBS ~0 Gs
100 mm	0.00 kg / 0.00 LBS 54 Gs	0.00 kg / 0.00 LBS 0 g / 0.0 N	0.00 kg / 0.00 LBS ~0 Gs

Two magnets 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 further horizon of action. Want to build a strong closure? Utilize two neodymiums instead of a neodymium and a striker plate. Exercise caution that when attracting two neodymiums, the impact force is massive. The levitation is marginally weaker than the connection force, but still large.
*The magnetic induction for N-N configuration drops to ~0 Gs at the geometric center between the magnets (due to field cancellation).
* Calculations refer to sliding force of dual matching neodymium magnets (friction coefficient ~0.15 for Ni-Ni layer).

Table 7: Hazards (electronics) - precautionary measures
MP 25x7.5/4.5x5 / N38

Object / Device	Limit (Gauss) / mT	Safe distance
Pacemaker	5 Gs (0.5 mT)	9.5 cm
Hearing aid	10 Gs (1.0 mT)	7.5 cm
Mechanical watch	20 Gs (2.0 mT)	6.0 cm
Phone / Smartphone	40 Gs (4.0 mT)	4.5 cm
Remote	50 Gs (5.0 mT)	4.0 cm
Payment card	400 Gs (40.0 mT)	2.0 cm
HDD hard drive	600 Gs (60.0 mT)	1.5 cm

Extremely neodym field is a real danger to electronic devices as well as medical implants. These NdFeB products generate a flux that destroys function of sensitive medical devices. Be aware: the unseen radiation acts through matter and plastic. Special caution must be exercised by people with hearing aids and drug dispensers. The risk also applies to: mechanical watches, car keys, speakers, and screens. Avoid contact with magnetic cards, HDD media, or precise measuring instruments.

Table 8: Impact energy (cracking risk) - collision effects
MP 25x7.5/4.5x5 / N38

Start from (mm)	Speed (km/h)	Energy (J)
10 mm	22.95 km/h (6.38 m/s)	0.36 J
30 mm	36.43 km/h (10.12 m/s)	0.91 J
50 mm	46.96 km/h (13.04 m/s)	1.52 J
100 mm	66.40 km/h (18.44 m/s)	3.03 J

NdFeB products are prone to chipping – a collision with steel risks their cracking. Watch the impact speed – a magnet released freely speeds with massive force. Kinetic force can trigger coating fragments or painful pinches to skin. Be sure to control the product during mounting so it doesn't hit with great force against the steel surface. A collision at high speed means shattering of the neodymium. Wear safety glasses when playing with powerful specimens.

Table 9: Coating parameters (durability)
MP 25x7.5/4.5x5 / 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)

The SST (salt spray test) is an industry standard for determining coating lifespan in harsh conditions. Moisture resistance is crucial for installations in bathrooms or outdoors.

Table 10: Electrical data (Flux)
MP 25x7.5/4.5x5 / N38

Parameter	Value	SI Unit / Description
Magnetic Flux	9 759 Mx	97.6 µWb
P_c Coefficient	0.25	Low (Flat)

Total magnetic flux emitted by the magnet pole. Key data in coil applications as well as sensors. P_c value defines the working geometry.

Table 11: Physics of underwater searching
MP 25x7.5/4.5x5 / N38

Environment	Effective steel pull	Effect
Air (land)	7.72 kg	Standard
Water (riverbed)	8.84 kg (+1.12 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.

The magnetic field penetrates through water without any losses. Note: for permanent underwater work, we recommend magnets with an anti-corrosive (epoxy) coating.

1. Vertical hold

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

2. Plate thickness effect

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

3. Heat tolerance

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

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

chart generated for the permeance coefficient P_c (Permeance Coefficient) = 0.25

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.

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: 030194-2026

Magnet Unit Converter

Force (pull)

Force in kg

Force in lbs

Magnetic Induction

Induction (T)

Just populate a single box, and the tool calculate the rest automatically.

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UMH 25x8x45 [M5] / N38 - magnetic holder with hook

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The ring magnet with a hole MP 25x7.5/4.5x5 / N38 is created for mechanical fastening, where glue might fail or be insufficient. Mounting is clean and reversible, unlike gluing. It is also often used in advertising for fixing signs and in workshops for organizing tools.

This is a crucial issue when working with model MP 25x7.5/4.5x5 / 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. 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 is not sufficient for rain. Damage to the protective layer during assembly is the most common cause of rusting. If you must use it outside, paint it with anti-corrosion paint after mounting.

The inner hole diameter determines the maximum size of the mounting element. 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. 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 5 mm. The pulling force of this model is an impressive 7.72 kg, which translates to 75.69 N in newtons. The mounting hole diameter is precisely 7.5/4.5 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). We do not offer paired sets with marked poles in this category, but they are easy to match manually.

Advantages and disadvantages of Nd₂Fe₁₄B magnets.

Advantages

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

They retain magnetic properties for around 10 years – the drop is just ~1% (according to analyses),
Neodymium magnets are characterized by exceptionally resistant to magnetic field loss caused by external magnetic fields,
A magnet with a shiny gold surface is more attractive,
Magnets have excellent magnetic induction on the outer layer,
Through (adequate) combination of ingredients, they can achieve high thermal resistance, allowing for action at temperatures approaching 230°C and above...
Possibility of accurate creating and optimizing to defined requirements,
Huge importance in future technologies – they are used in computer drives, electric motors, precision medical tools, also industrial machines.
Thanks to efficiency per cm³, small magnets offer high operating force, occupying minimum space,

Weaknesses

Problematic aspects of neodymium magnets: application proposals

Susceptibility to cracking is one of their disadvantages. Upon intense impact they can fracture. We recommend keeping them in a steel housing, which not only protects them against impacts but also increases their durability
Neodymium magnets demagnetize when exposed to high temperatures. After reaching 80°C, many of them experience permanent weakening of power (a factor is the shape as well as dimensions of the magnet). We offer magnets specially adapted to work at temperatures up to 230°C marked [AH], which are extremely resistant to heat
They rust in a humid environment. For use outdoors we suggest using waterproof magnets e.g. in rubber, plastic
Limited ability of making nuts in the magnet and complex forms - recommended is cover - mounting mechanism.
Potential hazard resulting from small fragments of magnets are risky, in case of ingestion, which gains importance in the context of child safety. It is also worth noting that small components of these magnets are able to complicate diagnosis medical when they are in the body.
Higher cost of purchase is a significant factor to consider compared to ceramic magnets, especially in budget applications

Holding force characteristics

Highest magnetic holding force – what it depends on?

The force parameter is a measurement result conducted under specific, ideal conditions:

on a block made of structural steel, effectively closing the magnetic field
whose thickness equals approx. 10 mm
characterized by even structure
with direct contact (without impurities)
under perpendicular force direction (90-degree angle)
in stable room temperature

Determinants of practical lifting force of a magnet

Holding efficiency is influenced by working environment parameters, such as (from priority):

Clearance – the presence of foreign body (rust, dirt, gap) acts as an insulator, which lowers capacity steeply (even by 50% at 0.5 mm).
Force direction – note that the magnet holds strongest perpendicularly. Under shear forces, the capacity drops drastically, often to levels of 20-30% of the maximum value.
Element thickness – for full efficiency, the steel must be adequately massive. Thin sheet restricts the attraction force (the magnet "punches through" it).
Steel grade – ideal substrate is pure iron steel. Stainless steels may generate lower lifting capacity.
Plate texture – smooth surfaces ensure maximum contact, which increases field saturation. Rough surfaces reduce efficiency.
Thermal environment – temperature increase results in weakening of force. It is worth remembering the thermal limit for a given model.

Lifting capacity testing was performed on a smooth plate of suitable thickness, under a perpendicular pulling force, however under attempts to slide the magnet the load capacity is reduced by as much as 5 times. Moreover, even a small distance between the magnet’s surface and the plate reduces the load capacity.

Warnings

Precision electronics

Navigation devices and mobile phones are extremely sensitive to magnetic fields. Direct contact with a strong magnet can decalibrate the sensors in your phone.

Powerful field

Before starting, check safety instructions. Uncontrolled attraction can destroy the magnet or injure your hand. Be predictive.

Magnet fragility

Watch out for shards. Magnets can explode upon uncontrolled impact, launching sharp fragments into the air. Eye protection is mandatory.

Danger to pacemakers

Warning for patients: Powerful magnets affect medical devices. Maintain minimum 30 cm distance or request help to work with the magnets.

Do not give to children

Always store magnets away from children. Risk of swallowing is high, and the consequences of magnets connecting inside the body are very dangerous.

Keep away from computers

Intense magnetic fields can erase data on payment cards, hard drives, and other magnetic media. Keep a distance of at least 10 cm.

Nickel coating and allergies

Warning for allergy sufferers: The Ni-Cu-Ni coating contains nickel. If an allergic reaction happens, immediately stop handling magnets and wear gloves.

Thermal limits

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

Bodily injuries

Protect your hands. Two large magnets will join instantly with a force of several hundred kilograms, crushing everything in their path. Be careful!

Fire risk

Drilling and cutting of neodymium magnets poses a fire hazard. Magnetic powder reacts violently with oxygen and is hard to extinguish.

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

MP 25x7.5/4.5x5 / N38 - ring magnet

Technical data of the product - MP 25x7.5/4.5x5 / N38 - ring magnet

Magnetic properties of material N38

Physical properties of sintered neodymium magnets Nd2Fe14B at 20°C

Engineering analysis of the magnet - data

Table 1: Static force (pull vs distance) - characteristics MP 25x7.5/4.5x5 / N38

Table 2: Slippage capacity (vertical surface) MP 25x7.5/4.5x5 / N38

Table 3: Wall mounting (shearing) - behavior on slippery surfaces MP 25x7.5/4.5x5 / N38

Table 4: Material efficiency (saturation) - sheet metal selection MP 25x7.5/4.5x5 / N38

Table 5: Thermal stability (material behavior) - thermal limit MP 25x7.5/4.5x5 / N38

Table 6: Magnet-Magnet interaction (repulsion) - forces in the system MP 25x7.5/4.5x5 / N38

Table 7: Hazards (electronics) - precautionary measures MP 25x7.5/4.5x5 / N38

Table 8: Impact energy (cracking risk) - collision effects MP 25x7.5/4.5x5 / N38

Table 9: Coating parameters (durability) MP 25x7.5/4.5x5 / N38

Table 10: Electrical data (Flux) MP 25x7.5/4.5x5 / N38

Table 11: Physics of underwater searching MP 25x7.5/4.5x5 / N38

1. Vertical hold

2. Plate thickness effect

3. Heat tolerance

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

Chemical composition

Ecology and recycling (GPSR)

Force (pull)

Magnetic Induction

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Advantages and disadvantages of Nd2Fe14B magnets.

Advantages

Weaknesses

Holding force characteristics

Highest magnetic holding force – what it depends on?

Determinants of practical lifting force of a magnet

Warnings

Precision electronics

Powerful field

Magnet fragility

Danger to pacemakers

Do not give to children

Keep away from computers

Nickel coating and allergies

Thermal limits

Bodily injuries

Fire risk

Physical properties of sintered neodymium magnets Nd₂Fe₁₄B at 20°C

Table 1: Static force (pull vs distance) - characteristics
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Table 2: Slippage capacity (vertical surface)
MP 25x7.5/4.5x5 / N38

Table 3: Wall mounting (shearing) - behavior on slippery surfaces
MP 25x7.5/4.5x5 / N38

Table 4: Material efficiency (saturation) - sheet metal selection
MP 25x7.5/4.5x5 / N38

Table 5: Thermal stability (material behavior) - thermal limit
MP 25x7.5/4.5x5 / N38

Table 6: Magnet-Magnet interaction (repulsion) - forces in the system
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Table 7: Hazards (electronics) - precautionary measures
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Table 8: Impact energy (cracking risk) - collision effects
MP 25x7.5/4.5x5 / N38

Table 9: Coating parameters (durability)
MP 25x7.5/4.5x5 / N38

Table 10: Electrical data (Flux)
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Table 11: Physics of underwater searching
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Advantages and disadvantages of Nd₂Fe₁₄B magnets.