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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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Strength along with appearance of a neodymium magnet can be calculated using our power calculator.

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Physical properties - 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

Physical analysis of the assembly - report

The following values represent the result of a mathematical analysis. Values are based on models for the class Nd₂Fe₁₄B. Real-world conditions might slightly deviate from the simulation results. Please consider these data as a supplementary guide during assembly planning.

Table 1: Static pull force (force vs gap) - power drop
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	medium risk
1 mm	1906 Gs 190.6 mT	7.05 kg / 15.54 lbs 7049.4 g / 69.2 N	medium risk
2 mm	1793 Gs 179.3 mT	6.24 kg / 13.75 lbs 6236.8 g / 61.2 N	medium risk
3 mm	1664 Gs 166.4 mT	5.37 kg / 11.84 lbs 5368.9 g / 52.7 N	medium risk
5 mm	1385 Gs 138.5 mT	3.72 kg / 8.21 lbs 3722.8 g / 36.5 N	medium risk
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 sharply with every mm of spacing. Keep in mind that even a microscopic distance (e.g., contamination, paint, veneer) noticeably weakens the grip. Magnetic products hold strongest at the point of direct contact; air break kills the power. Notice how flashily the parameters plummet, when the magnet does not touch tightly to the metal substrate. When calculating the mounting, eliminate redundant distances.

Table 2: Shear 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 calculates the estimated shear load sufficient to cause the sliding of the magnet downwards along a upright steel plate (assuming typical friction). This value depends on the separation distance between the magnet and the metal.

Table 3: Wall mounting (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 element on a upright wall (e.g., a fridge), it will maintain only about 1/5 of its maximum pull force. Gravity and a weak degree of grip cause that magnets move down faster than they detach. Designing a wall mount? Remember that the shear force is significantly lower than the perpendicular breakaway force. On a painted metal, the element will give way down under a significantly smaller weight. Using a rubber pad can significantly increase the grip.

Table 4: Steel thickness (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 cannot take in the full magnetic flux, which weakens actual performance of the magnet. Should you install a neodymium to a too thin substrate, the field will penetrate right through and the pull force will drop sharply. To utilize full efficiency of this neodymium's power, you require a sufficiently solid backing of steel. The saturation effect means that on thin elements (e.g., car bodies), the product shows lower pull force. We recommend selecting the steel cross-section based on the following data.

Table 5: Working in heat (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 power after exceeding the maximum temperature. Watch out for overheating – excessive heat can permanently damage this magnet. With every degree above norm, the neodymium's force momentarily drops. Refrain from using this magnet near heat sources exceeding its safe range. Too high temperature will result in irreversible degradation of magnetic properties.

*Important note: Heat tolerance depends not only on the material grade, as well as the dimension ratios. Thin magnets (low permeance coefficient) are more susceptible to demagnetization under lower heat stress compared to rod magnets. Red status in the table indicates permanent field degradation for this particular item.

Table 6: Two magnets (repulsion) - forces in the system
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 strong neodymiums attract each other from a significantly greater distance than a neodymium and metal combination. The connection of magnet-to-magnet produces a massive flux and a larger range of performance. Planning to create a solid fastener? Utilize two neodymiums instead of a neodymium and a steel. Remember that when connecting a pair of magnets, the pinch force is massive. The repulsion force is slightly lower than the attraction, but still significant.
*Flux density between like poles reaches ~0 Gs at the geometric center between the magnets (due to field cancellation).
Note: Results apply to shear force of dual same magnets (friction ~0.15 for Ni-Ni plating).

Table 7: Safety (HSE) (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
Phone / Smartphone	40 Gs (4.0 mT)	4.5 cm
Car key	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 is a real danger to electronic devices as well as medical implants. These magnets generate a flux that disrupts operation of digital equipment. Be aware: the unseen radiation acts through matter and glass. Increased vigilance must be taken by people with hearing aids and drug dispensers. The risk also applies to: mechanical watches, car keys, membranes, and displays. Do not place the magnet near cards, hard drives, or sensitive navigation tools.

Table 8: Collisions (kinetic energy) - 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 delicate – a violent impact against metal risks their cracking. Control the attraction moment – a neodymium left loose becomes dangerous. Striking energy can trigger coating fragments or dangerous crushing to fingers. Always hold the magnet during installation so it doesn't slam with momentum 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: Surface protection spec
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 following table defines the conditions under which this product can be safely used. Note the thickness of the protective layer.

Table 10: Electrical 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)

Total magnetic flux emitted by the pole surface. Essential parameter when building generators as well as sensors. The P_c coefficient defines the magnet's operating point.

Table 11: Underwater work (magnet fishing)
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%

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

In water, the magnet feels stronger thanks to Archimedes' principle. Buoyancy helps in lifting finds.

1. Wall mount (shear)

*Caution: On a vertical wall, the magnet holds just a fraction of its max power.

2. Steel thickness impact

*Thin steel (e.g. 0.5mm PC case) significantly weakens the holding force.

3. Power loss vs temp

*For N38 material, 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 specification and ecology

Material specification

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

Ecology and recycling (GPSR)

recyclability (EoL)	100%
recycled raw materials	~10% (pre-cons)
carbon footprint	low / zredukowany
waste code (EWC)	16 02 16

Safety card (GPSR)

responsible entity

Dhit sp. z o.o.

ul. Kościuszki 6A, 05-850 Ożarów Mazowiecki

tel: +48 22 499 98 98 | e-mail: bok@dhit.pl

batch number/type

id: 030194-2026

Measurement Calculator

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Kilograms (kg)

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The ring-shaped magnet MP 25x7.5/4.5x5 / N38 is created for permanent mounting, where glue might fail or be insufficient. Thanks to the hole (often for a screw), this model enables easy screwing 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 very brittle and inelastic. One turn too many can destroy the magnet, so do it slowly. The flat screw head should evenly press the magnet. Remember: cracking during assembly results from material properties, not a product defect.

These magnets are coated with standard Ni-Cu-Ni plating, which protects them in indoor conditions, but is not sufficient for rain. In the place of the mounting hole, the coating is thinner and easily scratched when tightening the screw, which will become a corrosion focus. This product is dedicated for inside building 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.

This model is characterized by dimensions Ø25x5 mm and a weight of 17.81 g. 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.

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. We do not offer paired sets with marked poles in this category, but they are easy to match manually.

Pros as well as cons of rare earth magnets.

Pros

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

They have constant strength, and over nearly 10 years their attraction force decreases symbolically – ~1% (in testing),
They show high resistance to demagnetization induced by external magnetic fields,
By covering with a shiny layer of gold, the element has an aesthetic look,
Neodymium magnets generate maximum magnetic induction on a small area, which increases force concentration,
Made from properly selected components, these magnets show impressive resistance to high heat, enabling them to function (depending on their form) at temperatures up to 230°C and above...
Considering the potential of flexible shaping and adaptation to individualized requirements, NdFeB magnets can be created in a broad palette of forms and dimensions, which amplifies use scope,
Key role in electronics industry – they are commonly used in mass storage devices, motor assemblies, diagnostic systems, as well as other advanced devices.
Thanks to their power density, small magnets offer high operating force, in miniature format,

Cons

Disadvantages of NdFeB magnets:

To avoid cracks under impact, we recommend using special steel housings. Such a solution protects the magnet and simultaneously increases its durability.
NdFeB magnets lose power when exposed to high temperatures. After reaching 80°C, many of them experience permanent weakening of strength (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 oxidize in a humid environment - during use outdoors we suggest using waterproof magnets e.g. in rubber, plastic
We recommend a housing - magnetic mechanism, due to difficulties in producing nuts inside the magnet and complicated shapes.
Possible danger related to microscopic parts of magnets are risky, when accidentally swallowed, which becomes key in the context of child safety. Furthermore, small elements of these devices are able to complicate diagnosis medical in case of swallowing.
With large orders the cost of neodymium magnets is economically unviable,

Lifting parameters

Maximum magnetic pulling force – what it depends on?

Information about lifting capacity is the result of a measurement for ideal contact conditions, assuming:

using a sheet made of low-carbon steel, acting as a ideal flux conductor
possessing a massiveness of minimum 10 mm to avoid saturation
with a surface free of scratches
without the slightest air gap between the magnet and steel
during detachment in a direction perpendicular to the plane
in temp. approx. 20°C

Lifting capacity in real conditions – factors

In practice, the actual lifting capacity results from several key aspects, ranked from crucial:

Clearance – the presence of foreign body (paint, tape, gap) acts as an insulator, which lowers power steeply (even by 50% at 0.5 mm).
Pull-off angle – remember that the magnet has greatest strength perpendicularly. Under sliding down, the capacity drops significantly, often to levels of 20-30% of the maximum value.
Base massiveness – too thin plate does not accept the full field, causing part of the power to be escaped to the other side.
Steel type – mild steel gives the best results. Alloy steels lower magnetic permeability and holding force.
Plate texture – smooth surfaces guarantee perfect abutment, which improves field saturation. Rough surfaces weaken the grip.
Temperature influence – high temperature reduces pulling force. Exceeding the limit temperature can permanently demagnetize the magnet.

Lifting capacity testing was performed on plates with a smooth surface of optimal thickness, under perpendicular forces, in contrast under parallel forces the load capacity is reduced by as much as 5 times. Moreover, even a small distance between the magnet’s surface and the plate lowers the lifting capacity.

Safety rules for work with NdFeB magnets

GPS Danger

Navigation devices and mobile phones are highly sensitive to magnetism. Close proximity with a powerful NdFeB magnet can permanently damage the sensors in your phone.

Demagnetization risk

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

Combustion hazard

Fire warning: Rare earth powder is highly flammable. Do not process magnets without safety gear as this risks ignition.

Crushing force

Mind your fingers. Two large magnets will snap together immediately with a force of massive weight, destroying everything in their path. Exercise extreme caution!

Keep away from computers

Equipment safety: Neodymium magnets can damage data carriers and sensitive devices (pacemakers, hearing aids, timepieces).

Conscious usage

Use magnets with awareness. Their immense force can shock even experienced users. Be vigilant and respect their power.

Skin irritation risks

Studies show that the nickel plating (the usual finish) is a common allergen. For allergy sufferers, prevent direct skin contact and choose encased magnets.

Adults only

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

Pacemakers

Life threat: Neodymium magnets can deactivate pacemakers and defibrillators. Stay away if you have medical devices.

Risk of cracking

Despite the nickel coating, neodymium is delicate and cannot withstand shocks. Avoid impacts, as the magnet may shatter into sharp, dangerous pieces.

Warning! Learn more about hazards in the article: Safety of working with magnets.

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

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

Magnetic properties of material N38

Physical properties of sintered neodymium magnets Nd2Fe14B at 20°C

Physical analysis of the assembly - report

Table 1: Static pull force (force vs gap) - power drop MP 25x7.5/4.5x5 / N38

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

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

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

Table 5: Working in heat (material behavior) - thermal limit MP 25x7.5/4.5x5 / N38

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

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

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

Table 9: Surface protection spec MP 25x7.5/4.5x5 / N38

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

Table 11: Underwater work (magnet fishing) MP 25x7.5/4.5x5 / N38

1. Wall mount (shear)

2. Steel thickness impact

3. Power loss vs temp

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

Material specification

Ecology and recycling (GPSR)

Pulling force

Magnetic Induction

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MW 5x1 / N38 - cylindrical magnet

Pros as well as cons of rare earth magnets.

Pros

Cons

Lifting parameters

Maximum magnetic pulling force – what it depends on?

Lifting capacity in real conditions – factors

Safety rules for work with NdFeB magnets

GPS Danger

Demagnetization risk

Combustion hazard

Crushing force

Keep away from computers

Conscious usage

Skin irritation risks

Adults only

Pacemakers

Risk of cracking

Physical properties of sintered neodymium magnets Nd₂Fe₁₄B at 20°C

Table 1: Static pull force (force vs gap) - power drop
MP 25x7.5/4.5x5 / N38

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

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

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

Table 5: Working in heat (material behavior) - thermal limit
MP 25x7.5/4.5x5 / N38

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

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

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

Table 9: Surface protection spec
MP 25x7.5/4.5x5 / N38

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

Table 11: Underwater work (magnet fishing)
MP 25x7.5/4.5x5 / N38