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MP 25x13x4 / N38 - ring magnet

Name: Dhit sp. z o.o.
Address: Kościuszki 6A, Ożarów Mazowiecki, Poland, 05-850, PL
Telephone: +48 22 499 98 98
Price range: PLN 1-6500
Rating: 5

ring magnet

Catalog no 030190

GTIN/EAN: 5906301812074

5.00

Diameter

25 mm [±0,1 mm]

internal diameter Ø

13 mm [±0,1 mm]

Height

4 mm [±0,1 mm]

Weight

10.74 g

Magnetization Direction

↑ axial

Load capacity

4.14 kg / 40.57 N

Magnetic Induction

188.92 mT / 1889 Gs

Coating

[NiCuNi] Nickel

see technical data »

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Technical of the product - MP 25x13x4 / N38 - ring magnet

Specification / characteristics - MP 25x13x4 / N38 - ring magnet

properties

properties	values
Cat. no.	030190
GTIN/EAN	5906301812074
Production/Distribution	Dhit sp. z o.o. ul. Zielona 14 05-850 Ożarów Mazowiecki PL
Country of origin	Poland / China / Germany
Customs code	85059029
Diameter	25 mm [±0,1 mm]
internal diameter Ø	13 mm [±0,1 mm]
Height	4 mm [±0,1 mm]
Weight	10.74 g
Magnetization Direction	↑ axial
Load capacity ~ ?	4.14 kg / 40.57 N
Magnetic Induction ~ ?	188.92 mT / 1889 Gs
Coating	[NiCuNi] Nickel
Manufacturing Tolerance	±0.1 mm

Magnetic properties of material N38

Specification / characteristics MP 25x13x4 / N38 - ring magnet

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

Physical properties of sintered neodymium magnets Nd₂Fe₁₄B at 20°C

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

Engineering analysis of the assembly - report

The following values represent the result of a engineering simulation. Values rely on algorithms for the class Nd₂Fe₁₄B. Operational performance may deviate from the simulation results. Treat these data as a reference point during assembly planning.

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

Distance (mm)	Induction (Gauss) / mT	Pull Force (kg/lbs/g/N)	Risk Status
0 mm	5777 Gs 577.7 mT	4.14 kg / 9.13 pounds 4140.0 g / 40.6 N	strong
1 mm	5310 Gs 531.0 mT	3.50 kg / 7.71 pounds 3497.4 g / 34.3 N	strong
2 mm	4846 Gs 484.6 mT	2.91 kg / 6.42 pounds 2912.4 g / 28.6 N	strong
3 mm	4397 Gs 439.7 mT	2.40 kg / 5.29 pounds 2398.5 g / 23.5 N	strong
5 mm	3576 Gs 357.6 mT	1.59 kg / 3.50 pounds 1586.2 g / 15.6 N	weak grip
10 mm	2073 Gs 207.3 mT	0.53 kg / 1.17 pounds 532.9 g / 5.2 N	weak grip
15 mm	1231 Gs 123.1 mT	0.19 kg / 0.41 pounds 188.0 g / 1.8 N	weak grip
20 mm	773 Gs 77.3 mT	0.07 kg / 0.16 pounds 74.0 g / 0.7 N	weak grip
30 mm	356 Gs 35.6 mT	0.02 kg / 0.03 pounds 15.7 g / 0.2 N	weak grip
50 mm	115 Gs 11.5 mT	0.00 kg / 0.00 pounds 1.6 g / 0.0 N	weak grip

Magnetic force drops significantly per each millimeter of distance. Remember that even a very thin break (e.g., contamination, paint, veneer) significantly weakens the grip. Neodymiums hold most effectively at the point of direct contact; distance weakens the force. Observe how rapidly the pull force fall, when the magnet does not adhere tightly to the steel surface. When designing the arrangement, eliminate unnecessary gaps.

Table 2: Slippage capacity (vertical surface)
MP 25x13x4 / N38

Distance (mm)	Friction coefficient	Pull Force (kg/lbs/g/N)
0 mm	Stal (~0.2)	0.83 kg / 1.83 pounds 828.0 g / 8.1 N
1 mm	Stal (~0.2)	0.70 kg / 1.54 pounds 700.0 g / 6.9 N
2 mm	Stal (~0.2)	0.58 kg / 1.28 pounds 582.0 g / 5.7 N
3 mm	Stal (~0.2)	0.48 kg / 1.06 pounds 480.0 g / 4.7 N
5 mm	Stal (~0.2)	0.32 kg / 0.70 pounds 318.0 g / 3.1 N
10 mm	Stal (~0.2)	0.11 kg / 0.23 pounds 106.0 g / 1.0 N
15 mm	Stal (~0.2)	0.04 kg / 0.08 pounds 38.0 g / 0.4 N
20 mm	Stal (~0.2)	0.01 kg / 0.03 pounds 14.0 g / 0.1 N
30 mm	Stal (~0.2)	0.00 kg / 0.01 pounds 4.0 g / 0.0 N
50 mm	Stal (~0.2)	0.00 kg / 0.00 pounds 0.0 g / 0.0 N

The following data defines the theoretical shear load required to cause the downward movement of the magnet down against a upright metal surface (assuming standard friction). This value is a function of the gap size between the magnet and the surface.

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

Surface type	Friction coefficient / % Mocy	Max load (kg/lbs/g/N)
Raw steel	µ = 0.3 30% Nominalnej Siły	1.24 kg / 2.74 pounds 1242.0 g / 12.2 N
Painted steel (standard)	µ = 0.2 20% Nominalnej Siły	0.83 kg / 1.83 pounds 828.0 g / 8.1 N
Oily/slippery steel	µ = 0.1 10% Nominalnej Siły	0.41 kg / 0.91 pounds 414.0 g / 4.1 N
Magnet with anti-slip rubber	µ = 0.5 50% Nominalnej Siły	2.07 kg / 4.56 pounds 2070.0 g / 20.3 N

When placing a element on a vertical wall (e.g., a board), it will maintain just approx. 20%-30% of nominal attraction strength. Gravity as well as a low friction coefficient influence the fact that holders slip faster than they pop off the substrate. Planning a vertical fastening? Remember that the sliding force is much weaker than the perpendicular breakaway force. On a slippery surface, the magnet will slip down under a noticeably lighter cargo. Using a rubber pad can effectively improve the result.

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

Steel thickness (mm)	% power	Real pull force (kg/lbs/g/N)
0.5 mm	10%	0.41 kg / 0.91 pounds 414.0 g / 4.1 N
1 mm	25%	1.04 kg / 2.28 pounds 1035.0 g / 10.2 N
2 mm	50%	2.07 kg / 4.56 pounds 2070.0 g / 20.3 N
3 mm	75%	3.10 kg / 6.85 pounds 3105.0 g / 30.5 N
5 mm	100%	4.14 kg / 9.13 pounds 4140.0 g / 40.6 N
10 mm	100%	4.14 kg / 9.13 pounds 4140.0 g / 40.6 N
11 mm	100%	4.14 kg / 9.13 pounds 4140.0 g / 40.6 N
12 mm	100%	4.14 kg / 9.13 pounds 4140.0 g / 40.6 N

A thin sheet cannot take in the full magnetic flux, which weakens actual performance of the magnet. If you install a neodymium to a too thin substrate, the magnetism will penetrate right through and the attraction force will be weaker. To utilize the maximum of this magnet's potential, you need a suitably thick piece of steel. The material oversaturation means that on sheet metal structures (e.g., thin profiles), the product shows lower pull force. We recommend selecting the steel dimension based on the following data.

Table 5: Working in heat (stability) - thermal limit
MP 25x13x4 / N38

Ambient temp. (°C)	Power loss	Remaining pull (kg/lbs/g/N)	Status
20 °C	0.0%	4.14 kg / 9.13 pounds 4140.0 g / 40.6 N	OK
40 °C	-2.2%	4.05 kg / 8.93 pounds 4048.9 g / 39.7 N	OK
60 °C	-4.4%	3.96 kg / 8.73 pounds 3957.8 g / 38.8 N	OK
80 °C	-6.6%	3.87 kg / 8.52 pounds 3866.8 g / 37.9 N
100 °C	-28.8%	2.95 kg / 6.50 pounds 2947.7 g / 28.9 N

Ordinary NdFeB products irreversibly lose strength after exceeding the maximum temperature. Protect against heat – excessive heat can irreversibly damage this magnet. With increasing heat, the magnet's power temporarily drops. Do not use this magnet in hot environments exceeding its working range. Too high temperature will result in destruction of magnetic properties.

*Technical advisory: Thermal stability depends not only on the material grade, as well as the dimension ratios. Thin magnets (low permeance coefficient) are more susceptible to demagnetization sooner than long magnets. Warning indicator in the table points to a risk of irreversible loss for this particular item.

Table 6: Magnet-Magnet interaction (repulsion) - forces in the system
MP 25x13x4 / N38

Gap (mm)	Attraction (kg/lbs) (N-S)	Lateral Force (kg/lbs/g/N)	Repulsion (kg/lbs) (N-N)
0 mm	83.66 kg / 184.44 pounds 6 082 Gs	12.55 kg / 27.67 pounds 12549 g / 123.1 N	N/A
1 mm	77.09 kg / 169.95 pounds 11 091 Gs	11.56 kg / 25.49 pounds 11563 g / 113.4 N	69.38 kg / 152.95 pounds ~0 Gs
2 mm	70.68 kg / 155.81 pounds 10 620 Gs	10.60 kg / 23.37 pounds 10601 g / 104.0 N	63.61 kg / 140.23 pounds ~0 Gs
3 mm	64.59 kg / 142.40 pounds 10 153 Gs	9.69 kg / 21.36 pounds 9689 g / 95.0 N	58.13 kg / 128.16 pounds ~0 Gs
5 mm	53.48 kg / 117.90 pounds 9 238 Gs	8.02 kg / 17.68 pounds 8022 g / 78.7 N	48.13 kg / 106.11 pounds ~0 Gs
10 mm	32.05 kg / 70.66 pounds 7 152 Gs	4.81 kg / 10.60 pounds 4808 g / 47.2 N	28.85 kg / 63.60 pounds ~0 Gs
20 mm	10.77 kg / 23.74 pounds 4 145 Gs	1.62 kg / 3.56 pounds 1615 g / 15.8 N	9.69 kg / 21.37 pounds ~0 Gs
50 mm	0.66 kg / 1.45 pounds 1 024 Gs	0.10 kg / 0.22 pounds 99 g / 1.0 N	0.59 kg / 1.30 pounds ~0 Gs
60 mm	0.32 kg / 0.70 pounds 712 Gs	0.05 kg / 0.10 pounds 48 g / 0.5 N	0.29 kg / 0.63 pounds ~0 Gs
70 mm	0.17 kg / 0.36 pounds 514 Gs	0.02 kg / 0.05 pounds 25 g / 0.2 N	0.15 kg / 0.33 pounds ~0 Gs
80 mm	0.09 kg / 0.20 pounds 383 Gs	0.01 kg / 0.03 pounds 14 g / 0.1 N	0.08 kg / 0.18 pounds ~0 Gs
90 mm	0.05 kg / 0.12 pounds 293 Gs	0.01 kg / 0.02 pounds 8 g / 0.1 N	0.05 kg / 0.11 pounds ~0 Gs
100 mm	0.03 kg / 0.07 pounds 230 Gs	0.00 kg / 0.01 pounds 5 g / 0.0 N	0.03 kg / 0.07 pounds ~0 Gs

Two strong neodymiums interact from a much further distance than a magnet and sheet setup. The connection of two magnets generates a stronger field and a further horizon of action. Want to build a solid fastener? Apply two magnets instead of one magnet and a striker plate. Exercise caution that when bringing together two magnets, the impact force is huge. The levitation is a bit weaker than the connection force, but still significant.
*The magnetic induction for N-N configuration is approximately ~0 Gs at the geometric center between the magnets (due to field cancellation).
Attention: Calculations apply to sliding force of a pair of matching magnets (friction coefficient ~0.15 for Ni-Ni plating).

Table 7: Safety (HSE) (electronics) - warnings
MP 25x13x4 / N38

Object / Device	Limit (Gauss) / mT	Safe distance
Pacemaker	5 Gs (0.5 mT)	17.0 cm
Hearing aid	10 Gs (1.0 mT)	13.5 cm
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

Extremely neodym field is a large risk to electronic devices as well as pacemakers. These magnets generate a field that prevents correct functioning of sensitive medical devices. Remember: the unseen radiation penetrates the body and plastic. Special caution must be taken by people with hearing aids and drug dispensers. Also at risk are: mechanical watches, car keys, speakers, and screens. Do not place the magnet near cards, HDD media, or precise measuring instruments.

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

Start from (mm)	Speed (km/h)	Energy (J)
10 mm	21.33 km/h (5.93 m/s)	0.19 J
30 mm	34.38 km/h (9.55 m/s)	0.49 J
50 mm	44.29 km/h (12.30 m/s)	0.81 J
100 mm	62.62 km/h (17.39 m/s)	1.62 J

Magnetic elements are very brittle – a strong collision with metal risks their cracking. Pay attention to connection velocity – a magnet released freely speeds with massive force. Kinetic force can trigger coating fragments or injury to fingers. Always hold the magnet during installation so it doesn't hit with great force against the metal. A collision at high speed means shattering of the magnet. Wear eye protection when playing with powerful specimens.

Table 9: Corrosion resistance
MP 25x13x4 / N38

Technical parameter	Value / Description
Coating type	[NiCuNi] Nickel
Layer structure	Nickel - Copper - Nickel
Layer thickness	10-20 µm
Salt spray test (SST) ?	24 h
Recommended environment	Indoors only (dry)

Neodymium magnets are highly susceptible to corrosion without proper protection. Note the thickness of the protective layer.

Table 10: Electrical data (Flux)
MP 25x13x4 / N38

Parameter	Value	SI Unit / Description
Magnetic Flux	24 861 Mx	248.6 µWb
P_c Coefficient	1.02	High (Stable)

Flux value passing through the magnet pole. Key data when building generators as well as sensors. The P_c coefficient determines the magnet's operating point.

Table 11: Physics of underwater searching
MP 25x13x4 / N38

Environment	Effective steel pull	Effect
Air (land)	4.14 kg	Standard
Water (riverbed)	4.74 kg (+0.60 kg buoyancy gain)	+14.5%

Corrosion warning: This magnet has a standard nickel coating. After use in water, it must be dried and maintained immediately, otherwise it will rust!

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

1. Sliding resistance

*Note: On a vertical surface, the magnet holds only a fraction of its max power.

2. Efficiency vs thickness

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

3. Thermal stability

*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) = 1.02

The chart above illustrates the magnetic characteristics of the material within the second quadrant of the hysteresis loop. 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

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: 030190-2026

Magnet Unit Converter

Magnet pull force

Force (N)

lbs

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Gauss (Gs)

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The ring magnet with a hole MP 25x13x4 / N38 is created for mechanical fastening, where glue might fail or be insufficient. Thanks to the hole (often for a screw), this model enables quick installation to wood, wall, plastic, or metal. This product with a force of 4.14 kg works great as a door latch, speaker holder, or mounting element in devices.

This is a crucial issue when working with model MP 25x13x4 / N38. Neodymium magnets are sintered ceramics, which means they are very brittle and inelastic. One turn too many can destroy the magnet, so do it slowly. The flat screw head should evenly press the magnet. Remember: cracking during assembly results from material properties, not a product defect.

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.

A screw or bolt with a thread diameter smaller than 13 mm fits this model. For magnets with a straight hole, a conical head can act like a wedge and burst the magnet. 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.

It is a magnetic ring with a diameter of 25 mm and thickness 4 mm. The pulling force of this model is an impressive 4.14 kg, which translates to 40.57 N in newtons. The product has a [NiCuNi] coating and is made of NdFeB material. Inner hole dimension: 13 mm.

The poles are located on the planes with holes, not on the sides of the ring. In the case of connecting two rings, make sure one is turned the right way. When ordering a larger quantity, magnets are usually packed in stacks, where they are already naturally paired.

Strengths as well as weaknesses of neodymium magnets.

Strengths

In addition to their long-term stability, neodymium magnets provide the following advantages:

Their strength is durable, and after approximately ten years it drops only by ~1% (theoretically),
They feature excellent resistance to weakening of magnetic properties when exposed to external fields,
The use of an refined layer of noble metals (nickel, gold, silver) causes the element to be more visually attractive,
Magnets are characterized by maximum magnetic induction on the outer side,
Due to their durability and thermal resistance, neodymium magnets are capable of operate (depending on the shape) even at high temperatures reaching 230°C or more...
Thanks to freedom in designing and the ability to adapt to complex applications,
Significant place in future technologies – they serve a role in computer drives, electric motors, medical devices, and technologically advanced constructions.
Thanks to their power density, small magnets offer high operating force, in miniature format,

Disadvantages

Disadvantages of neodymium magnets:

Brittleness is one of their disadvantages. Upon intense impact they can break. We recommend keeping them in a special holder, 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 very resistant to heat
They oxidize in a humid environment - during use outdoors we advise using waterproof magnets e.g. in rubber, plastic
Due to limitations in producing nuts and complex forms in magnets, we recommend using casing - magnetic holder.
Potential hazard to health – tiny shards of magnets can be dangerous, when accidentally swallowed, which becomes key in the aspect of protecting the youngest. It is also worth noting that small elements of these magnets are able to be problematic in diagnostics medical in case of swallowing.
High unit price – neodymium magnets cost more than other types of magnets (e.g. ferrite), which can limit application in large quantities

Pull force analysis

Optimal lifting capacity of a neodymium magnet – what it depends on?

Breakaway force was defined for ideal contact conditions, including:

on a block made of mild steel, optimally conducting the magnetic field
possessing a massiveness of minimum 10 mm to avoid saturation
with an ideally smooth touching surface
under conditions of no distance (surface-to-surface)
for force applied at a right angle (pull-off, not shear)
at standard ambient temperature

Determinants of lifting force in real conditions

Please note that the application force will differ subject to the following factors, starting with the most relevant:

Distance – existence of foreign body (paint, tape, gap) acts as an insulator, which lowers power rapidly (even by 50% at 0.5 mm).
Force direction – declared lifting capacity refers to pulling vertically. When applying parallel force, the magnet holds much less (often approx. 20-30% of maximum force).
Substrate thickness – to utilize 100% power, the steel must be adequately massive. Paper-thin metal limits the lifting capacity (the magnet "punches through" it).
Steel grade – ideal substrate is pure iron steel. Hardened steels may have worse magnetic properties.
Plate texture – smooth surfaces ensure maximum contact, which increases force. Uneven metal reduce efficiency.
Thermal factor – hot environment reduces magnetic field. Exceeding the limit temperature can permanently damage the magnet.

Lifting capacity testing was conducted on plates with a smooth surface of suitable thickness, under a perpendicular pulling force, whereas under attempts to slide the magnet the load capacity is reduced by as much as 5 times. Additionally, even a minimal clearance between the magnet and the plate lowers the lifting capacity.

Precautions when working with NdFeB magnets

Permanent damage

Watch the temperature. Exposing the magnet to high heat will ruin its properties and pulling force.

Protective goggles

Protect your eyes. Magnets can explode upon violent connection, ejecting sharp fragments into the air. We recommend safety glasses.

Phone sensors

An intense magnetic field interferes with the functioning of magnetometers in phones and GPS navigation. Do not bring magnets near a device to prevent damaging the sensors.

Flammability

Drilling and cutting of NdFeB material poses a fire risk. Magnetic powder oxidizes rapidly with oxygen and is hard to extinguish.

Life threat

Warning for patients: Powerful magnets affect medical devices. Maintain at least 30 cm distance or ask another person to work with the magnets.

Keep away from children

Only for adults. Tiny parts pose a choking risk, causing intestinal necrosis. Store away from children and animals.

Crushing force

Watch your fingers. Two powerful magnets will snap together immediately with a force of several hundred kilograms, destroying everything in their path. Be careful!

Data carriers

Powerful magnetic fields can erase data on payment cards, HDDs, and storage devices. Stay away of at least 10 cm.

Sensitization to coating

Warning for allergy sufferers: The nickel-copper-nickel coating contains nickel. If skin irritation happens, immediately stop handling magnets and use protective gear.

Do not underestimate power

Exercise caution. Neodymium magnets attract from a long distance and connect with massive power, often faster than you can move away.

Attention! Want to know more? Read our article: Are neodymium magnets dangerous?

MP 25x13x4 / N38 - ring magnet

Technical of the product - MP 25x13x4 / N38 - ring magnet

Magnetic properties of material N38

Physical properties of sintered neodymium magnets Nd2Fe14B at 20°C

Engineering analysis of the assembly - report

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

Table 2: Slippage capacity (vertical surface) MP 25x13x4 / N38

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

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

Table 5: Working in heat (stability) - thermal limit MP 25x13x4 / N38

Table 6: Magnet-Magnet interaction (repulsion) - forces in the system MP 25x13x4 / N38

Table 7: Safety (HSE) (electronics) - warnings MP 25x13x4 / N38

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

Table 9: Corrosion resistance MP 25x13x4 / N38

Table 10: Electrical data (Flux) MP 25x13x4 / N38

Table 11: Physics of underwater searching MP 25x13x4 / N38

1. Sliding resistance

2. Efficiency vs thickness

3. Thermal stability

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

Elemental analysis

Sustainability

Magnet pull force

Field Strength

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Strengths as well as weaknesses of neodymium magnets.

Strengths

Disadvantages

Pull force analysis

Optimal lifting capacity of a neodymium magnet – what it depends on?

Determinants of lifting force in real conditions

Precautions when working with NdFeB magnets

Permanent damage

Protective goggles

Phone sensors

Flammability

Life threat

Keep away from children

Crushing force

Data carriers

Sensitization to coating

Do not underestimate power

Physical properties of sintered neodymium magnets Nd₂Fe₁₄B at 20°C

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

Table 2: Slippage capacity (vertical surface)
MP 25x13x4 / N38

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

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

Table 5: Working in heat (stability) - thermal limit
MP 25x13x4 / N38

Table 6: Magnet-Magnet interaction (repulsion) - forces in the system
MP 25x13x4 / N38

Table 7: Safety (HSE) (electronics) - warnings
MP 25x13x4 / N38

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

Table 9: Corrosion resistance
MP 25x13x4 / N38

Table 10: Electrical data (Flux)
MP 25x13x4 / N38

Table 11: Physics of underwater searching
MP 25x13x4 / N38