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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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Detailed specification - 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 modeling of the product - data

The following data constitute the result of a physical calculation. Results rely on models for the material Nd₂Fe₁₄B. Actual parameters may differ from theoretical values. Treat these data as a supplementary guide for designers.

Table 1: Static pull force (pull vs distance) - interaction chart
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

Grip strength weakens significantly with every subsequent millimeter of spacing. Keep in mind that even the smallest gap (e.g., contamination, paint, dust) strongly reduces the pull force. Magnetic products work optimally at the point of direct contact; gap kills the power. Observe how quickly the parameters fall, when the product does not adhere tightly to the steel surface. When planning the mounting, discard redundant distances.

Table 2: Vertical 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 following data indicates the estimated holding capacity necessary to cause the sliding of the magnet vertically on a vertical steel wall (assuming typical friction). The holding force varies with the separation distance between the magnet and the metal.

Table 3: Vertical assembly (sliding) - vertical pull
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 holder on a vertical wall (e.g., a board), it will maintain just approx. 1/5 of its maximum pull force. Gravitational force as well as a low friction coefficient cause that products move down faster than they pull off. Want to create a vertical fastening? Remember that the sliding force is noticeably lower than the maximum static pull force. On a smooth steel, the element will slip down under a noticeably lighter weight. Using a rubber pad can effectively raise the stability.

Table 4: Steel thickness (substrate influence) - 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 take in the full magnetic flux, which squanders power of the holder. If you mount a strong magnet to a thin surface, the magnetism will pass right through and the holding will be smaller. To squeeze the maximum of this neodymium's potential, you need a suitably thick backing of steel. The material oversaturation means that on thin elements (e.g., thin profiles), the holder works worse. We recommend selecting 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

Classic neodymiums irreversibly lose strength above the temperature limit. Avoid high temperatures – high temperature can permanently destroy this magnet. As the temperature rises, the neodymium's power temporarily drops. Do not use this product close to ovens exceeding its working range. Ignoring the limit will lead to irreversible degradation of magnetic properties.

*Important note: Temperature resistance is determined by both grade, but also on the magnet's shape. Low-profile magnets (low permeance coefficient) risk losing magnetic properties sooner compared to rod magnets. The danger warning in the table points to permanent field degradation for this specific geometry.

Table 6: Magnet-Magnet interaction (attraction) - field collision
MP 25x7.5/4.5x5 / N38

Gap (mm)	Attraction (kg/lbs) (N-S)	Lateral 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 magnetic products interact from a significantly greater distance than a neodymium and metal setup. The setup of magnet-to-magnet creates a more powerful interaction and a further horizon of performance. Planning to create a strong closure? Use a pair of magnets instead of a neodymium and a steel. Exercise caution that when attracting two neodymiums, the collision energy is extreme. The levitation is a bit weaker than the connection force, but still large.
*Flux density in repulsion mode drops to ~0 Gs at the geometric center between the magnets (due to field cancellation).
* Results apply to sliding force of dual matching magnets (friction ~0.15 for Ni-Ni coating).

Table 7: Protective zones (implants) - 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
Mobile device	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

Powerful magnet radiation poses a serious hazard to electronics and medical implants. These NdFeB products generate a flux that destroys function of digital equipment. Be aware: the invisible magnetic field penetrates the body and housings. Special caution must be taken by people with cochlear implants and drug dispensers. The risk also applies to: mechanical watches, remotes, membranes, and displays. Avoid contact with magnetic cards, hard drives, or precise measuring instruments.

Table 8: Collisions (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

Neodymium magnets are very brittle – a violent impact against metal can result in shattering. Watch the impact speed – a neodymium left loose becomes dangerous. Kinetic force can destroy the magnet or injury to fingers. Be sure to control the product during installation so it doesn't hit violently against the steel surface. A collision at high speed almost guarantees destruction of the magnet. Wear safety glasses when working with powerful specimens.

Table 9: Corrosion resistance
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. Note the thickness of the protective layer.

Table 10: Construction data (P_c)
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)

Flux value passing through the pole surface. Key data for generator designers and motors. P_c value determines 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%

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

In water, the magnet feels stronger thanks to Archimedes' principle. Note: for permanent underwater work, we recommend magnets with an anti-corrosive (epoxy) coating.

1. Vertical hold

*Warning: On a vertical surface, the magnet retains just ~20% of its max power.

2. Efficiency vs thickness

*Thin steel (e.g. computer case) severely limits the holding force.

3. Heat tolerance

*For N38 grade, the safety 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

Elemental analysis

iron (Fe)	64% – 68%
neodymium (Nd)	29% – 32%
boron (B)	1.1% – 1.2%
dysprosium (Dy)	0.5% – 2.0%
coating (Ni-Cu-Ni)	< 0.05%

Sustainability

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

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UMC 20x6/3x7 / N38 - cylindrical magnetic holder

6.99 ZŁ brutto / pcs

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 7.72 kg works great as a door latch, speaker holder, or spacer element in devices.

This is a crucial issue when working with model MP 25x7.5/4.5x5 / N38. Neodymium magnets are sintered ceramics, which means they are hard but breakable and inelastic. When tightening the screw, you must maintain great sensitivity. We recommend tightening manually with a screwdriver, not an impact driver, because too much pressure will cause the ring to crack. 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 indoor use. For outdoor applications, we recommend choosing rubberized holders or additional protection with varnish.

The inner hole diameter determines the maximum size of the mounting element. 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.

The presented product is a ring magnet with dimensions Ø25 mm (outer diameter) and height 5 mm. The key parameter here is the lifting capacity amounting to approximately 7.72 kg (force ~75.69 N). The product has a [NiCuNi] coating and is made of NdFeB material. Inner hole dimension: 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.

Strengths and weaknesses of neodymium magnets.

Advantages

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

They have stable power, and over around 10 years their performance decreases symbolically – ~1% (in testing),
Neodymium magnets are characterized by highly resistant to loss of magnetic properties caused by external interference,
In other words, due to the reflective layer of silver, the element gains visual value,
Neodymium magnets achieve maximum magnetic induction on a small area, which ensures high operational effectiveness,
Neodymium magnets are characterized by extremely high magnetic induction on the magnet surface and are able to act (depending on the form) even at a temperature of 230°C or more...
Considering the possibility of accurate molding and adaptation to unique needs, neodymium magnets can be produced in a wide range of shapes and sizes, which expands the range of possible applications,
Fundamental importance in high-tech industry – they are utilized in HDD drives, drive modules, medical devices, as well as modern systems.
Thanks to their power density, small magnets offer high operating force, occupying minimum space,

Disadvantages

Drawbacks and weaknesses of neodymium magnets: tips and applications.

To avoid cracks under impact, we recommend using special steel housings. Such a solution secures the magnet and simultaneously increases its durability.
When exposed to high temperature, neodymium magnets suffer a drop in strength. Often, when the temperature exceeds 80°C, their strength decreases (depending on the size, as well as shape of the magnet). For those who need magnets for extreme conditions, we offer [AH] versions withstanding up to 230°C
When exposed to humidity, magnets usually rust. For applications 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 holder, due to difficulties in creating nuts inside the magnet and complicated shapes.
Possible danger resulting from small fragments of magnets can be dangerous, if swallowed, which gains importance in the context of child safety. Additionally, small elements of these magnets can be problematic in diagnostics medical when they are in the body.
Higher cost of purchase is one of the disadvantages compared to ceramic magnets, especially in budget applications

Pull force analysis

Magnetic strength at its maximum – what contributes to it?

Holding force of 7.72 kg is a theoretical maximum value conducted under standard conditions:

on a base made of structural steel, effectively closing the magnetic field
possessing a thickness of minimum 10 mm to avoid saturation
characterized by smoothness
with zero gap (no coatings)
during detachment in a direction vertical to the plane
at conditions approx. 20°C

Determinants of lifting force in real conditions

Effective lifting capacity impacted by working environment parameters, including (from most important):

Distance – the presence of any layer (paint, tape, gap) interrupts the magnetic circuit, which lowers capacity rapidly (even by 50% at 0.5 mm).
Force direction – declared lifting capacity refers to detachment vertically. When slipping, the magnet exhibits much less (typically approx. 20-30% of maximum force).
Plate thickness – too thin sheet does not close the flux, causing part of the flux to be lost into the air.
Plate material – low-carbon steel gives the best results. Higher carbon content reduce magnetic permeability and lifting capacity.
Plate texture – smooth surfaces guarantee perfect abutment, which improves field saturation. Uneven metal reduce efficiency.
Temperature influence – high temperature weakens pulling force. Too high temperature can permanently damage the magnet.

Lifting capacity was measured by applying a steel plate with a smooth surface of optimal thickness (min. 20 mm), under vertically applied force, in contrast under parallel forces the load capacity is reduced by as much as 5 times. In addition, even a minimal clearance between the magnet’s surface and the plate reduces the load capacity.

Safety rules for work with NdFeB magnets

Conscious usage

Use magnets with awareness. Their powerful strength can surprise even professionals. Stay alert and respect their force.

Cards and drives

Do not bring magnets close to a wallet, computer, or screen. The magnetism can permanently damage these devices and erase data from cards.

Do not give to children

Always store magnets out of reach of children. Choking hazard is high, and the effects of magnets clamping inside the body are life-threatening.

ICD Warning

Patients with a ICD have to keep an large gap from magnets. The magnetism can disrupt the operation of the life-saving device.

Risk of cracking

NdFeB magnets are sintered ceramics, meaning they are fragile like glass. Clashing of two magnets leads to them shattering into small pieces.

Sensitization to coating

It is widely known that the nickel plating (standard magnet coating) is a strong allergen. If your skin reacts to metals, avoid direct skin contact and opt for encased magnets.

GPS Danger

A powerful magnetic field interferes with the operation of magnetometers in phones and GPS navigation. Do not bring magnets near a device to prevent breaking the sensors.

Bodily injuries

Danger of trauma: The attraction force is so great that it can cause blood blisters, pinching, and even bone fractures. Protective gloves are recommended.

Flammability

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

Power loss in heat

Keep cool. Neodymium magnets are susceptible to temperature. If you need resistance above 80°C, look for HT versions (H, SH, UH).

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

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

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

Magnetic properties of material N38

Physical properties of sintered neodymium magnets Nd2Fe14B at 20°C

Engineering modeling of the product - data

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

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

Table 3: Vertical assembly (sliding) - vertical pull MP 25x7.5/4.5x5 / N38

Table 4: Steel thickness (substrate influence) - 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 (attraction) - field collision MP 25x7.5/4.5x5 / N38

Table 7: Protective zones (implants) - precautionary measures MP 25x7.5/4.5x5 / N38

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

Table 9: Corrosion resistance MP 25x7.5/4.5x5 / N38

Table 10: Construction data (Pc) MP 25x7.5/4.5x5 / N38

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

1. Vertical hold

2. Efficiency vs thickness

3. Heat tolerance

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

Elemental analysis

Sustainability

Force (pull)

Magnetic Induction

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Strengths and weaknesses of neodymium magnets.

Advantages

Disadvantages

Pull force analysis

Magnetic strength at its maximum – what contributes to it?

Determinants of lifting force in real conditions

Safety rules for work with NdFeB magnets

Conscious usage

Cards and drives

Do not give to children

ICD Warning

Risk of cracking

Sensitization to coating

GPS Danger

Bodily injuries

Flammability

Power loss in heat

Physical properties of sintered neodymium magnets Nd₂Fe₁₄B at 20°C

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

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

Table 3: Vertical assembly (sliding) - vertical pull
MP 25x7.5/4.5x5 / N38

Table 4: Steel thickness (substrate influence) - 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 (attraction) - field collision
MP 25x7.5/4.5x5 / N38

Table 7: Protective zones (implants) - precautionary measures
MP 25x7.5/4.5x5 / N38

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

Table 9: Corrosion resistance
MP 25x7.5/4.5x5 / N38

Table 10: Construction data (P_c)
MP 25x7.5/4.5x5 / N38

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