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MP 25x7x9 / 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 030195

GTIN/EAN: 5906301812128

5.00

Diameter

25 mm [±0,1 mm]

internal diameter Ø

7 mm [±0,1 mm]

Height

9 mm [±0,1 mm]

Weight

30.54 g

Magnetization Direction

↑ axial

Load capacity

14.82 kg / 145.39 N

Magnetic Induction

362.13 mT / 3621 Gs

Coating

[NiCuNi] Nickel

technical parameters »

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Physical properties - MP 25x7x9 / N38 - ring magnet

Specification / characteristics - MP 25x7x9 / N38 - ring magnet

properties

properties	values
Cat. no.	030195
GTIN/EAN	5906301812128
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 mm [±0,1 mm]
Height	9 mm [±0,1 mm]
Weight	30.54 g
Magnetization Direction	↑ axial
Load capacity ~ ?	14.82 kg / 145.39 N
Magnetic Induction ~ ?	362.13 mT / 3621 Gs
Coating	[NiCuNi] Nickel
Manufacturing Tolerance	±0.1 mm

Magnetic properties of material N38

Specification / characteristics MP 25x7x9 / 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 magnet - technical parameters

Presented values are the outcome of a engineering calculation. Values were calculated on models for the material Nd₂Fe₁₄B. Real-world performance might slightly deviate from the simulation results. Use these calculations as a reference point when designing systems.

Table 1: Static force (pull vs gap) - characteristics
MP 25x7x9 / N38

Distance (mm)	Induction (Gauss) / mT	Pull Force (kg/lbs/g/N)	Risk Status
0 mm	5777 Gs 577.7 mT	14.82 kg / 32.67 lbs 14820.0 g / 145.4 N	dangerous!
1 mm	5310 Gs 531.0 mT	12.52 kg / 27.60 lbs 12519.6 g / 122.8 N	dangerous!
2 mm	4846 Gs 484.6 mT	10.43 kg / 22.98 lbs 10425.5 g / 102.3 N	dangerous!
3 mm	4397 Gs 439.7 mT	8.59 kg / 18.93 lbs 8586.1 g / 84.2 N	strong
5 mm	3576 Gs 357.6 mT	5.68 kg / 12.52 lbs 5678.0 g / 55.7 N	strong
10 mm	2073 Gs 207.3 mT	1.91 kg / 4.21 lbs 1907.5 g / 18.7 N	weak grip
15 mm	1231 Gs 123.1 mT	0.67 kg / 1.48 lbs 673.1 g / 6.6 N	weak grip
20 mm	773 Gs 77.3 mT	0.27 kg / 0.58 lbs 265.0 g / 2.6 N	weak grip
30 mm	356 Gs 35.6 mT	0.06 kg / 0.12 lbs 56.2 g / 0.6 N	weak grip
50 mm	115 Gs 11.5 mT	0.01 kg / 0.01 lbs 5.9 g / 0.1 N	weak grip

Grip strength decreases significantly with every mm of distance. Keep in mind that every additional insulation layer (e.g., contamination, varnish, veneer) strongly weakens the grip. Neodymiums hold strongest during direct contact; distance kills the power. Observe how flashily the pull force fall, when the product does not touch directly to the metal substrate. When designing the assembly, avoid unnecessary gaps.

Table 2: Shear hold (vertical surface)
MP 25x7x9 / N38

Distance (mm)	Friction coefficient	Pull Force (kg/lbs/g/N)
0 mm	Stal (~0.2)	2.96 kg / 6.53 lbs 2964.0 g / 29.1 N
1 mm	Stal (~0.2)	2.50 kg / 5.52 lbs 2504.0 g / 24.6 N
2 mm	Stal (~0.2)	2.09 kg / 4.60 lbs 2086.0 g / 20.5 N
3 mm	Stal (~0.2)	1.72 kg / 3.79 lbs 1718.0 g / 16.9 N
5 mm	Stal (~0.2)	1.14 kg / 2.50 lbs 1136.0 g / 11.1 N
10 mm	Stal (~0.2)	0.38 kg / 0.84 lbs 382.0 g / 3.7 N
15 mm	Stal (~0.2)	0.13 kg / 0.30 lbs 134.0 g / 1.3 N
20 mm	Stal (~0.2)	0.05 kg / 0.12 lbs 54.0 g / 0.5 N
30 mm	Stal (~0.2)	0.01 kg / 0.03 lbs 12.0 g / 0.1 N
50 mm	Stal (~0.2)	0.00 kg / 0.00 lbs 2.0 g / 0.0 N

This section calculates the theoretical holding capacity sufficient to initiate the downward movement of the magnet vertically against a upright steel wall (assuming typical friction coefficient). The holding force varies with the separation distance between the magnet and the metal.

Table 3: Vertical assembly (sliding) - behavior on slippery surfaces
MP 25x7x9 / N38

Surface type	Friction coefficient / % Mocy	Max load (kg/lbs/g/N)
Raw steel	µ = 0.3 30% Nominalnej Siły	4.45 kg / 9.80 lbs 4446.0 g / 43.6 N
Painted steel (standard)	µ = 0.2 20% Nominalnej Siły	2.96 kg / 6.53 lbs 2964.0 g / 29.1 N
Oily/slippery steel	µ = 0.1 10% Nominalnej Siły	1.48 kg / 3.27 lbs 1482.0 g / 14.5 N
Magnet with anti-slip rubber	µ = 0.5 50% Nominalnej Siły	7.41 kg / 16.34 lbs 7410.0 g / 72.7 N

When placing a element on a vertical plane (e.g., a car body), it will only hold only approx. 1/5 of its nominal power. Gravity and a weak degree of grip influence the fact that holders move down easier than they pop off the substrate. Planning a hanger? Consider that the sliding force is much weaker than the maximum static pull force. On a smooth steel, the magnet will slip down under a significantly smaller cargo. Using a rubber layer can drastically increase the grip.

Table 4: Steel thickness (substrate influence) - sheet metal selection
MP 25x7x9 / N38

Steel thickness (mm)	% power	Real pull force (kg/lbs/g/N)
0.5 mm	5%	0.74 kg / 1.63 lbs 741.0 g / 7.3 N
1 mm	13%	1.85 kg / 4.08 lbs 1852.5 g / 18.2 N
2 mm	25%	3.71 kg / 8.17 lbs 3705.0 g / 36.3 N
3 mm	38%	5.56 kg / 12.25 lbs 5557.5 g / 54.5 N
5 mm	63%	9.26 kg / 20.42 lbs 9262.5 g / 90.9 N
10 mm	100%	14.82 kg / 32.67 lbs 14820.0 g / 145.4 N
11 mm	100%	14.82 kg / 32.67 lbs 14820.0 g / 145.4 N
12 mm	100%	14.82 kg / 32.67 lbs 14820.0 g / 145.4 N

A thin metal plate is not enough to absorb the full magnetic flux, which weakens actual performance of the holder. Should you attach a powerful product to a thin surface, the magnetism will pass right through and the attraction force will be weaker. To achieve 100% of this magnet's potential, you require a sufficiently solid backing of metal. The material oversaturation means that on sheet metal structures (e.g., car bodies), the holder works worse. We recommend selecting the steel dimension based on the following data.

Table 5: Thermal resistance (material behavior) - resistance threshold
MP 25x7x9 / N38

Ambient temp. (°C)	Power loss	Remaining pull (kg/lbs/g/N)	Status
20 °C	0.0%	14.82 kg / 32.67 lbs 14820.0 g / 145.4 N	OK
40 °C	-2.2%	14.49 kg / 31.95 lbs 14494.0 g / 142.2 N	OK
60 °C	-4.4%	14.17 kg / 31.23 lbs 14167.9 g / 139.0 N	OK
80 °C	-6.6%	13.84 kg / 30.52 lbs 13841.9 g / 135.8 N
100 °C	-28.8%	10.55 kg / 23.26 lbs 10551.8 g / 103.5 N

Classic neodymiums irreversibly lose parameters above the temperature limit. Protect against heat – heat can permanently destroy this product. With increasing heat, the magnet's force briefly drops. Do not use this magnet close to heaters exceeding its safe range. Too high temperature will lead to permanent loss of magnetism.

*Technical advisory: Heat tolerance depends not only on the material grade, as well as the dimension ratios. Thin magnets (low Pc) are more susceptible to demagnetization sooner than long magnets. The danger warning in the table signals permanent field degradation for this specific geometry.

Table 6: Two magnets (attraction) - field collision
MP 25x7x9 / N38

Gap (mm)	Attraction (kg/lbs) (N-S)	Shear Strength (kg/lbs/g/N)	Repulsion (kg/lbs) (N-N)
0 mm	74.73 kg / 164.76 lbs 6 082 Gs	11.21 kg / 24.71 lbs 11210 g / 110.0 N	N/A
1 mm	68.86 kg / 151.81 lbs 11 091 Gs	10.33 kg / 22.77 lbs 10329 g / 101.3 N	61.97 kg / 136.63 lbs ~0 Gs
2 mm	63.13 kg / 139.18 lbs 10 620 Gs	9.47 kg / 20.88 lbs 9470 g / 92.9 N	56.82 kg / 125.26 lbs ~0 Gs
3 mm	57.70 kg / 127.20 lbs 10 153 Gs	8.65 kg / 19.08 lbs 8654 g / 84.9 N	51.93 kg / 114.48 lbs ~0 Gs
5 mm	47.77 kg / 105.31 lbs 9 238 Gs	7.17 kg / 15.80 lbs 7165 g / 70.3 N	42.99 kg / 94.78 lbs ~0 Gs
10 mm	28.63 kg / 63.12 lbs 7 152 Gs	4.29 kg / 9.47 lbs 4295 g / 42.1 N	25.77 kg / 56.81 lbs ~0 Gs
20 mm	9.62 kg / 21.21 lbs 4 145 Gs	1.44 kg / 3.18 lbs 1443 g / 14.2 N	8.66 kg / 19.09 lbs ~0 Gs
50 mm	0.59 kg / 1.29 lbs 1 024 Gs	0.09 kg / 0.19 lbs 88 g / 0.9 N	0.53 kg / 1.16 lbs ~0 Gs
60 mm	0.28 kg / 0.62 lbs 712 Gs	0.04 kg / 0.09 lbs 43 g / 0.4 N	0.26 kg / 0.56 lbs ~0 Gs
70 mm	0.15 kg / 0.33 lbs 514 Gs	0.02 kg / 0.05 lbs 22 g / 0.2 N	0.13 kg / 0.29 lbs ~0 Gs
80 mm	0.08 kg / 0.18 lbs 383 Gs	0.01 kg / 0.03 lbs 12 g / 0.1 N	0.07 kg / 0.16 lbs ~0 Gs
90 mm	0.05 kg / 0.11 lbs 293 Gs	0.01 kg / 0.02 lbs 7 g / 0.1 N	0.04 kg / 0.10 lbs ~0 Gs
100 mm	0.03 kg / 0.07 lbs 230 Gs	0.00 kg / 0.01 lbs 4 g / 0.0 N	0.03 kg / 0.06 lbs ~0 Gs

Two magnetic products interact from a wider radius than a magnet and sheet combination. The connection of two magnets generates a stronger field and a further horizon of operation. Designing a solid fastener? Use a pair of magnets instead of one magnet and a steel. Be careful that when bringing together two magnets, the pinch force is extreme. The repulsion force is slightly lower than the connection force, but still impressive.
*Field value in repulsion mode reaches ~0 Gs at the geometric center of the gap (caused by magnetic field nullification).
Important: Figures refer to shear force of a pair of identical neodymium magnets (friction coefficient ~0.15 for Ni-Ni coating).

Table 7: Safety (HSE) (implants) - precautionary measures
MP 25x7x9 / 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
Mechanical watch	20 Gs (2.0 mT)	10.5 cm
Mobile device	40 Gs (4.0 mT)	8.0 cm
Car key	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

A strong magnetic field is a large risk to electronic devices as well as medical implants. These magnets produce a field that disrupts operation of sensitive medical devices. Be aware: the unseen radiation passes through tissues and housings. Special caution must be exercised by people with cochlear implants and insulin pumps. Also at risk are: automatic timepieces, remotes, speakers, and displays. Avoid contact with magnetic cards, HDD media, or sensitive navigation tools.

Table 8: Dynamics (kinetic energy) - collision effects
MP 25x7x9 / N38

Start from (mm)	Speed (km/h)	Energy (J)
10 mm	23.94 km/h (6.65 m/s)	0.68 J
30 mm	38.57 km/h (10.71 m/s)	1.75 J
50 mm	49.69 km/h (13.80 m/s)	2.91 J
100 mm	70.25 km/h (19.52 m/s)	5.82 J

NdFeB products are delicate – a violent impact against metal causes immediate chipping. Watch the impact speed – a magnet released freely turns into a projectile. Impact energy can destroy the magnet or injury to skin. Always hold the magnet during mounting so it doesn't hit violently against the metal. A collision at high speed ends with a crack of the magnet. Wear safety glasses when handling with large magnets.

Table 9: Corrosion resistance
MP 25x7x9 / 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)

Neodymium magnets are highly susceptible to corrosion without proper protection. Improper coating selection is the most common cause of magnet failure over time.

Table 10: Construction data (Flux)
MP 25x7x9 / N38

Parameter	Value	SI Unit / Description
Magnetic Flux	22 495 Mx	225.0 µWb
P_c Coefficient	1.05	High (Stable)

Total magnetic flux passing through the magnet pole. Essential parameter when building generators and motors. P_c value defines the magnet's operating point.

Table 11: Physics of underwater searching
MP 25x7x9 / N38

Environment	Effective steel pull	Effect
Air (land)	14.82 kg	Standard
Water (riverbed)	16.97 kg (+2.15 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.

Water displaces steel, making heavy objects slightly lighter. Buoyancy helps in lifting finds.

1. Vertical hold

*Caution: On a vertical surface, the magnet retains only a fraction of its nominal pull.

2. Steel thickness impact

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

3. Heat tolerance

*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) = 1.05

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

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: 030195-2026

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The ring-shaped magnet MP 25x7x9 / 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 material behaves more like porcelain than steel, so it doesn't forgive mistakes during mounting. 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. In the place of the mounting hole, the coating is thinner and easily scratched when tightening the screw, which will become a corrosion focus. 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 9 mm. The key parameter here is the holding force amounting to approximately 14.82 kg (force ~145.39 N). The mounting hole diameter is precisely 7 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.

Pros as well as cons of rare earth magnets.

Pros

Besides their durability, neodymium magnets are valued for these benefits:

They have unchanged lifting capacity, and over more than ten years their performance decreases symbolically – ~1% (in testing),
They are noted for resistance to demagnetization induced by external disturbances,
The use of an refined coating of noble metals (nickel, gold, silver) causes the element to be more visually attractive,
The surface of neodymium magnets generates a unique magnetic field – this is a key feature,
Neodymium magnets are characterized by extremely high magnetic induction on the magnet surface and are able to act (depending on the shape) even at a temperature of 230°C or more...
Possibility of exact machining as well as modifying to precise applications,
Universal use in electronics industry – they are utilized in mass storage devices, motor assemblies, medical devices, and multitasking production systems.
Relatively small size with high pulling force – neodymium magnets offer impressive pulling force in compact dimensions, which makes them useful in small systems

Limitations

Disadvantages of NdFeB magnets:

They are prone to damage upon heavy impacts. To avoid cracks, it is worth protecting magnets using a steel holder. Such protection not only protects the magnet but also improves its resistance to damage
Neodymium magnets lose strength when exposed to high temperatures. After reaching 80°C, many of them experience permanent drop 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 very resistant to heat
They oxidize in a humid environment - during use outdoors we advise using waterproof magnets e.g. in rubber, plastic
We recommend casing - magnetic mount, due to difficulties in realizing nuts inside the magnet and complex forms.
Possible danger related to microscopic parts of magnets can be dangerous, if swallowed, which gains importance in the context of child health protection. It is also worth noting that tiny parts of these devices are able to disrupt the diagnostic process medical in case of swallowing.
High unit price – neodymium magnets are more expensive than other types of magnets (e.g. ferrite), which hinders application in large quantities

Pull force analysis

Magnetic strength at its maximum – what affects it?

The load parameter shown concerns the limit force, recorded under optimal environment, meaning:

on a plate made of mild steel, perfectly concentrating the magnetic flux
with a thickness no less than 10 mm
with a plane perfectly flat
without the slightest clearance between the magnet and steel
during detachment in a direction vertical to the mounting surface
at temperature approx. 20 degrees Celsius

Lifting capacity in real conditions – factors

During everyday use, the real power results from several key aspects, listed from most significant:

Clearance – the presence of any layer (paint, dirt, air) acts as an insulator, which lowers capacity steeply (even by 50% at 0.5 mm).
Angle of force application – maximum parameter is reached only during perpendicular pulling. The shear force of the magnet along the surface is usually many times lower (approx. 1/5 of the lifting capacity).
Metal thickness – thin material does not allow full use of the magnet. Part of the magnetic field penetrates through instead of converting into lifting capacity.
Plate material – mild steel gives the best results. Higher carbon content lower magnetic permeability and holding force.
Surface structure – the smoother and more polished the surface, the better the adhesion and stronger the hold. Roughness acts like micro-gaps.
Thermal conditions – NdFeB sinters have a negative temperature coefficient. At higher temperatures they lose power, and at low temperatures they can be stronger (up to a certain limit).

Lifting capacity testing was performed on plates with a smooth surface of suitable thickness, under a perpendicular pulling force, in contrast under attempts to slide the magnet the holding force is lower. Additionally, even a minimal clearance between the magnet’s surface and the plate reduces the holding force.

H&S for magnets

Dust explosion hazard

Dust generated during machining of magnets is flammable. Do not drill into magnets unless you are an expert.

Threat to navigation

Note: neodymium magnets produce a field that disrupts precision electronics. Maintain a separation from your mobile, tablet, and GPS.

Do not give to children

Adult use only. Tiny parts pose a choking risk, causing severe trauma. Store away from children and animals.

Caution required

Before starting, check safety instructions. Uncontrolled attraction can destroy the magnet or hurt your hand. Think ahead.

Magnetic media

Equipment safety: Strong magnets can damage data carriers and delicate electronics (pacemakers, hearing aids, timepieces).

Maximum temperature

Regular neodymium magnets (grade N) lose magnetization when the temperature goes above 80°C. Damage is permanent.

Beware of splinters

Protect your eyes. Magnets can explode upon violent connection, ejecting shards into the air. Wear goggles.

Implant safety

Health Alert: Neodymium magnets can turn off heart devices and defibrillators. Do not approach if you have electronic implants.

Metal Allergy

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

Physical harm

Mind your fingers. Two powerful magnets will snap together immediately with a force of massive weight, crushing anything in their path. Be careful!

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

MP 25x7x9 / N38 - ring magnet

Physical properties - MP 25x7x9 / N38 - ring magnet

Magnetic properties of material N38

Physical properties of sintered neodymium magnets Nd2Fe14B at 20°C

Engineering modeling of the magnet - technical parameters

Table 1: Static force (pull vs gap) - characteristics MP 25x7x9 / N38

Table 2: Shear hold (vertical surface) MP 25x7x9 / N38

Table 3: Vertical assembly (sliding) - behavior on slippery surfaces MP 25x7x9 / N38

Table 4: Steel thickness (substrate influence) - sheet metal selection MP 25x7x9 / N38

Table 5: Thermal resistance (material behavior) - resistance threshold MP 25x7x9 / N38

Table 6: Two magnets (attraction) - field collision MP 25x7x9 / N38

Table 7: Safety (HSE) (implants) - precautionary measures MP 25x7x9 / N38

Table 8: Dynamics (kinetic energy) - collision effects MP 25x7x9 / N38

Table 9: Corrosion resistance MP 25x7x9 / N38

Table 10: Construction data (Flux) MP 25x7x9 / N38

Table 11: Physics of underwater searching MP 25x7x9 / N38

1. Vertical hold

2. Steel thickness impact

3. Heat tolerance

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

Elemental analysis

Sustainability

Magnet pull force

Magnetic Field

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Pros as well as cons of rare earth magnets.

Pros

Limitations

Pull force analysis

Magnetic strength at its maximum – what affects it?

Lifting capacity in real conditions – factors

H&S for magnets

Dust explosion hazard

Threat to navigation

Do not give to children

Caution required

Magnetic media

Maximum temperature

Beware of splinters

Implant safety

Metal Allergy

Physical harm

Physical properties of sintered neodymium magnets Nd₂Fe₁₄B at 20°C

Table 1: Static force (pull vs gap) - characteristics
MP 25x7x9 / N38

Table 2: Shear hold (vertical surface)
MP 25x7x9 / N38

Table 3: Vertical assembly (sliding) - behavior on slippery surfaces
MP 25x7x9 / N38

Table 4: Steel thickness (substrate influence) - sheet metal selection
MP 25x7x9 / N38

Table 5: Thermal resistance (material behavior) - resistance threshold
MP 25x7x9 / N38

Table 6: Two magnets (attraction) - field collision
MP 25x7x9 / N38

Table 7: Safety (HSE) (implants) - precautionary measures
MP 25x7x9 / N38

Table 8: Dynamics (kinetic energy) - collision effects
MP 25x7x9 / N38

Table 9: Corrosion resistance
MP 25x7x9 / N38

Table 10: Construction data (Flux)
MP 25x7x9 / N38

Table 11: Physics of underwater searching
MP 25x7x9 / N38