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MP 40x10.4/5.5x5 / 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 030249

GTIN/EAN: 5906301812258

5.00

Diameter

40 mm [±0,1 mm]

internal diameter Ø

10.4/5.5 mm [±0,1 mm]

Height

5 mm [±0,1 mm]

Weight

46.23 g

Magnetization Direction

↑ axial

Load capacity

9.47 kg / 92.86 N

Magnetic Induction

150.36 mT / 1504 Gs

Coating

[NiCuNi] Nickel

see technical specifications »

27.00 ZŁ with VAT / pcs + price for transport

21.95 ZŁ net + 23% VAT / pcs

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Detailed specification - MP 40x10.4/5.5x5 / N38 - ring magnet

Specification / characteristics - MP 40x10.4/5.5x5 / N38 - ring magnet

properties

properties	values
Cat. no.	030249
GTIN/EAN	5906301812258
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	40 mm [±0,1 mm]
internal diameter Ø	10.4/5.5 mm [±0,1 mm]
Height	5 mm [±0,1 mm]
Weight	46.23 g
Magnetization Direction	↑ axial
Load capacity ~ ?	9.47 kg / 92.86 N
Magnetic Induction ~ ?	150.36 mT / 1504 Gs
Coating	[NiCuNi] Nickel
Manufacturing Tolerance	±0.1 mm

Magnetic properties of material N38

Specification / characteristics MP 40x10.4/5.5x5 / 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 simulation of the assembly - data

The following values constitute the result of a mathematical calculation. Results were calculated on algorithms for the class Nd₂Fe₁₄B. Operational performance might slightly deviate from the simulation results. Use these data as a reference point when designing systems.

Table 1: Static force (force vs distance) - characteristics
MP 40x10.4/5.5x5 / N38

Distance (mm)	Induction (Gauss) / mT	Pull Force (kg/lbs/g/N)	Risk Status
0 mm	1289 Gs 128.9 mT	9.47 kg / 20.88 lbs 9470.0 g / 92.9 N	medium risk
1 mm	1265 Gs 126.5 mT	9.12 kg / 20.11 lbs 9120.9 g / 89.5 N	medium risk
2 mm	1232 Gs 123.2 mT	8.66 kg / 19.10 lbs 8662.7 g / 85.0 N	medium risk
3 mm	1193 Gs 119.3 mT	8.12 kg / 17.90 lbs 8121.3 g / 79.7 N	medium risk
5 mm	1099 Gs 109.9 mT	6.89 kg / 15.18 lbs 6887.8 g / 67.6 N	medium risk
10 mm	825 Gs 82.5 mT	3.88 kg / 8.56 lbs 3882.0 g / 38.1 N	medium risk
15 mm	580 Gs 58.0 mT	1.92 kg / 4.22 lbs 1915.5 g / 18.8 N	safe
20 mm	399 Gs 39.9 mT	0.91 kg / 2.00 lbs 908.3 g / 8.9 N	safe
30 mm	195 Gs 19.5 mT	0.22 kg / 0.48 lbs 217.6 g / 2.1 N	safe
50 mm	61 Gs 6.1 mT	0.02 kg / 0.05 lbs 21.0 g / 0.2 N	safe

Pulling power decreases significantly with every subsequent millimeter of distance. Note that even a microscopic distance (e.g., contamination, varnish, dust) noticeably weakens the grip. Magnetic products hold strongest in perfect adhesion; gap weakens the power. Observe how flashily the parameters drop, when the product does not adhere directly to the steel surface. When calculating the assembly, discard unnecessary gaps.

Table 2: Vertical hold (vertical surface)
MP 40x10.4/5.5x5 / N38

Distance (mm)	Friction coefficient	Pull Force (kg/lbs/g/N)
0 mm	Stal (~0.2)	1.89 kg / 4.18 lbs 1894.0 g / 18.6 N
1 mm	Stal (~0.2)	1.82 kg / 4.02 lbs 1824.0 g / 17.9 N
2 mm	Stal (~0.2)	1.73 kg / 3.82 lbs 1732.0 g / 17.0 N
3 mm	Stal (~0.2)	1.62 kg / 3.58 lbs 1624.0 g / 15.9 N
5 mm	Stal (~0.2)	1.38 kg / 3.04 lbs 1378.0 g / 13.5 N
10 mm	Stal (~0.2)	0.78 kg / 1.71 lbs 776.0 g / 7.6 N
15 mm	Stal (~0.2)	0.38 kg / 0.85 lbs 384.0 g / 3.8 N
20 mm	Stal (~0.2)	0.18 kg / 0.40 lbs 182.0 g / 1.8 N
30 mm	Stal (~0.2)	0.04 kg / 0.10 lbs 44.0 g / 0.4 N
50 mm	Stal (~0.2)	0.00 kg / 0.01 lbs 4.0 g / 0.0 N

The table below indicates the estimated shear load necessary to start the downward movement of the magnet down against a vertical metal surface (considering typical friction coefficient). The holding force varies with the air gap between the magnet and the surface.

Table 3: Wall mounting (shearing) - vertical pull
MP 40x10.4/5.5x5 / N38

Surface type	Friction coefficient / % Mocy	Max load (kg/lbs/g/N)
Raw steel	µ = 0.3 30% Nominalnej Siły	2.84 kg / 6.26 lbs 2841.0 g / 27.9 N
Painted steel (standard)	µ = 0.2 20% Nominalnej Siły	1.89 kg / 4.18 lbs 1894.0 g / 18.6 N
Oily/slippery steel	µ = 0.1 10% Nominalnej Siły	0.95 kg / 2.09 lbs 947.0 g / 9.3 N
Magnet with anti-slip rubber	µ = 0.5 50% Nominalnej Siły	4.74 kg / 10.44 lbs 4735.0 g / 46.5 N

When mounting a holder on a vertical plane (e.g., a fridge), it will maintain barely about 20%-30% of its nominal power. Gravitational force and a low friction coefficient cause that holders move down faster than they pop off the substrate. Designing a hanger? Consider that the shear force is noticeably lower than the perpendicular breakaway force. On a painted metal, the holder will give way down under a much lighter cargo. Using a rubber layer can effectively improve the result.

Table 4: Material efficiency (substrate influence) - sheet metal selection
MP 40x10.4/5.5x5 / N38

Steel thickness (mm)	% power	Real pull force (kg/lbs/g/N)
0.5 mm	10%	0.95 kg / 2.09 lbs 947.0 g / 9.3 N
1 mm	25%	2.37 kg / 5.22 lbs 2367.5 g / 23.2 N
2 mm	50%	4.74 kg / 10.44 lbs 4735.0 g / 46.5 N
3 mm	75%	7.10 kg / 15.66 lbs 7102.5 g / 69.7 N
5 mm	100%	9.47 kg / 20.88 lbs 9470.0 g / 92.9 N
10 mm	100%	9.47 kg / 20.88 lbs 9470.0 g / 92.9 N
11 mm	100%	9.47 kg / 20.88 lbs 9470.0 g / 92.9 N
12 mm	100%	9.47 kg / 20.88 lbs 9470.0 g / 92.9 N

A thin sheet cannot absorb the full magnetic flux, which wastes potential of the holder. If you mount a strong magnet to a too thin substrate, the field will pass right through and the pull force will drop sharply. To utilize 100% of this neodymium's potential, you need a suitably thick element of metal. The saturation phenomenon causes that on sheet metal structures (e.g., thin profiles), the holder works worse. We advise picking the steel cross-section based on the following data.

Table 5: Thermal resistance (stability) - thermal limit
MP 40x10.4/5.5x5 / N38

Ambient temp. (°C)	Power loss	Remaining pull (kg/lbs/g/N)	Status
20 °C	0.0%	9.47 kg / 20.88 lbs 9470.0 g / 92.9 N	OK
40 °C	-2.2%	9.26 kg / 20.42 lbs 9261.7 g / 90.9 N	OK
60 °C	-4.4%	9.05 kg / 19.96 lbs 9053.3 g / 88.8 N
80 °C	-6.6%	8.84 kg / 19.50 lbs 8845.0 g / 86.8 N
100 °C	-28.8%	6.74 kg / 14.86 lbs 6742.6 g / 66.1 N

Standard neodymium magnets lose power above the temperature limit. Avoid high temperatures – high temperature can irreversibly demagnetize this magnet. As the temperature rises, the magnet's power briefly decreases. Avoid using this product close to heaters exceeding its working range. Exceeding the critical threshold will result in permanent loss of magnetism.

*Engineering note: Thermal stability depends not only on the material grade, as well as the dimension ratios. Thin magnets (low permeance coefficient) may lose charge permanently under lower heat stress compared to rod magnets. Red status in the table points to permanent field degradation for this particular item.

Table 6: Magnet-Magnet interaction (repulsion) - field collision
MP 40x10.4/5.5x5 / N38

Gap (mm)	Attraction (kg/lbs) (N-S)	Shear Strength (kg/lbs/g/N)	Repulsion (kg/lbs) (N-N)
0 mm	10.73 kg / 23.65 lbs 2 424 Gs	1.61 kg / 3.55 lbs 1609 g / 15.8 N	N/A
1 mm	10.55 kg / 23.25 lbs 2 555 Gs	1.58 kg / 3.49 lbs 1582 g / 15.5 N	9.49 kg / 20.93 lbs ~0 Gs
2 mm	10.33 kg / 22.78 lbs 2 529 Gs	1.55 kg / 3.42 lbs 1550 g / 15.2 N	9.30 kg / 20.50 lbs ~0 Gs
3 mm	10.09 kg / 22.23 lbs 2 499 Gs	1.51 kg / 3.34 lbs 1513 g / 14.8 N	9.08 kg / 20.01 lbs ~0 Gs
5 mm	9.52 kg / 20.98 lbs 2 427 Gs	1.43 kg / 3.15 lbs 1427 g / 14.0 N	8.56 kg / 18.88 lbs ~0 Gs
10 mm	7.80 kg / 17.20 lbs 2 198 Gs	1.17 kg / 2.58 lbs 1170 g / 11.5 N	7.02 kg / 15.48 lbs ~0 Gs
20 mm	4.40 kg / 9.69 lbs 1 650 Gs	0.66 kg / 1.45 lbs 660 g / 6.5 N	3.96 kg / 8.72 lbs ~0 Gs
50 mm	0.49 kg / 1.09 lbs 553 Gs	0.07 kg / 0.16 lbs 74 g / 0.7 N	0.44 kg / 0.98 lbs ~0 Gs
60 mm	0.25 kg / 0.54 lbs 391 Gs	0.04 kg / 0.08 lbs 37 g / 0.4 N	0.22 kg / 0.49 lbs ~0 Gs
70 mm	0.13 kg / 0.28 lbs 282 Gs	0.02 kg / 0.04 lbs 19 g / 0.2 N	0.12 kg / 0.26 lbs ~0 Gs
80 mm	0.07 kg / 0.15 lbs 209 Gs	0.01 kg / 0.02 lbs 11 g / 0.1 N	0.06 kg / 0.14 lbs ~0 Gs
90 mm	0.04 kg / 0.09 lbs 158 Gs	0.01 kg / 0.01 lbs 6 g / 0.1 N	0.04 kg / 0.08 lbs ~0 Gs
100 mm	0.02 kg / 0.05 lbs 121 Gs	0.00 kg / 0.01 lbs 4 g / 0.0 N	0.02 kg / 0.05 lbs ~0 Gs

Two magnets attract each other from a wider radius than a neodymium and metal combination. The connection of two magnets creates a more powerful interaction and a wider radius of performance. Designing a solid fastener? Use a pair of magnets instead of one magnet and a striker plate. Remember that when bringing together two magnets, the collision energy is extreme. The repulsion force is slightly lower than the attraction, but still impressive.
*Flux density in repulsion mode drops to ~0 Gs at the geometric center between the magnets (due to field cancellation).
Note: Estimates refer to friction force of dual same neodymium magnets (friction ~0.15 for Ni-Ni coating).

Table 7: Protective zones (implants) - precautionary measures
MP 40x10.4/5.5x5 / N38

Object / Device	Limit (Gauss) / mT	Safe distance
Pacemaker	5 Gs (0.5 mT)	12.5 cm
Hearing aid	10 Gs (1.0 mT)	10.0 cm
Mechanical watch	20 Gs (2.0 mT)	8.0 cm
Phone / Smartphone	40 Gs (4.0 mT)	6.0 cm
Car key	50 Gs (5.0 mT)	5.5 cm
Payment card	400 Gs (40.0 mT)	2.0 cm
HDD hard drive	600 Gs (60.0 mT)	1.5 cm

A strong magnetic field poses a large risk to electronics and pacemakers. These neodymiums generate a field that disrupts operation of digital equipment. Notice: the invisible magnetic field acts through matter and plastic. Exceptional care must be exercised by people with cochlear implants and drug dispensers. The risk also applies to: automatic timepieces, remotes, membranes, and screens. Avoid contact with magnetic cards, hard drives, or sensitive navigation tools.

Table 8: Dynamics (kinetic energy) - warning
MP 40x10.4/5.5x5 / N38

Start from (mm)	Speed (km/h)	Energy (J)
10 mm	17.75 km/h (4.93 m/s)	0.56 J
30 mm	25.36 km/h (7.04 m/s)	1.15 J
50 mm	32.32 km/h (8.98 m/s)	1.86 J
100 mm	45.65 km/h (12.68 m/s)	3.72 J

Magnetic elements are delicate – a collision with steel risks their cracking. Watch the impact speed – a neodymium left loose speeds with massive force. Impact energy can trigger coating fragments or injury to fingers. Be sure to control the product during installation so it doesn't hit with great force against the steel surface. A collision at high speed means shattering of the magnet. Wear eye protection when working with powerful specimens.

Table 9: Coating parameters (durability)
MP 40x10.4/5.5x5 / 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)

Neodymium magnets are highly susceptible to corrosion without proper protection. Moisture resistance is crucial for installations in bathrooms or outdoors.

Table 10: Construction data (Flux)
MP 40x10.4/5.5x5 / N38

Parameter	Value	SI Unit / Description
Magnetic Flux	17 767 Mx	177.7 µWb
P_c Coefficient	0.17	Low (Flat)

Total magnetic flux passing through the pole surface. Essential parameter in coil applications as well as sensors. The P_c coefficient defines the working geometry.

Table 11: Physics of underwater searching
MP 40x10.4/5.5x5 / N38

Environment	Effective steel pull	Effect
Air (land)	9.47 kg	Standard
Water (riverbed)	10.84 kg (+1.37 kg buoyancy gain)	+14.5%

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

Water displaces steel, making heavy objects slightly lighter. Note: for permanent underwater work, we recommend magnets with an anti-corrosive (epoxy) coating.

1. Wall mount (shear)

*Caution: On a vertical wall, the magnet holds merely approx. 20-30% of its max power.

2. Steel saturation

*Thin metal sheet (e.g. computer case) severely weakens the holding force.

3. Power loss vs temp

*For N38 grade, the max working temp is 80°C.

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

chart generated for the permeance coefficient P_c (Permeance Coefficient) = 0.17

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 and environmental data

Chemical composition

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

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: 030249-2026

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The ring magnet with a hole MP 40x10.4/5.5x5 / N38 is created for permanent mounting, where glue might fail or be insufficient. Thanks to the hole (often for a screw), this model enables quick installation to wood, wall, plastic, or metal. It is also often used in advertising for fixing signs and in workshops for organizing tools.

This is a crucial issue when working with model MP 40x10.4/5.5x5 / N38. Neodymium magnets are sintered ceramics, which means they are hard but breakable and inelastic. One turn too many can destroy the magnet, so do it slowly. It's a good idea to use a rubber spacer under the screw head, which will cushion the stresses. Remember: cracking during assembly results from material properties, not a product defect.

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. This product is dedicated for inside building use. For outdoor applications, we recommend choosing rubberized holders or additional protection with varnish.

A screw or bolt with a thread diameter smaller than 10.4/5.5 mm fits this model. 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.

This model is characterized by dimensions Ø40x5 mm and a weight of 46.23 g. The pulling force of this model is an impressive 9.47 kg, which translates to 92.86 N in newtons. The mounting hole diameter is precisely 10.4/5.5 mm.

These magnets are magnetized axially (through the thickness), which means one flat side is the N pole and the other is S. 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.

Strengths and weaknesses of neodymium magnets.

Advantages

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

They virtually do not lose power, because even after 10 years the decline in efficiency is only ~1% (according to literature),
Magnets effectively resist against loss of magnetization caused by ambient magnetic noise,
By using a reflective coating of nickel, the element presents an elegant look,
Magnetic induction on the working layer of the magnet turns out to be strong,
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...
Thanks to the ability of free shaping and adaptation to specialized projects, magnetic components can be produced in a wide range of geometric configurations, which expands the range of possible applications,
Universal use in future technologies – they find application in hard drives, electric motors, advanced medical instruments, as well as industrial machines.
Thanks to their power density, small magnets offer high operating force, occupying minimum space,

Disadvantages

Disadvantages of neodymium magnets:

To avoid cracks upon strong impacts, we recommend using special steel holders. Such a solution secures the magnet and simultaneously improves its durability.
When exposed to high temperature, neodymium magnets experience a drop in force. Often, when the temperature exceeds 80°C, their power decreases (depending on the size and 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 start to rust. To use them in conditions outside, it is recommended to use protective magnets, such as those in rubber or plastics, which prevent oxidation as well as corrosion.
Limited ability of making nuts in the magnet and complex shapes - recommended is a housing - magnetic holder.
Possible danger resulting from small fragments of magnets are risky, when accidentally swallowed, which becomes key in the aspect of protecting the youngest. Additionally, small components of these products can complicate diagnosis medical after entering the body.
Due to complex production process, their price is relatively high,

Pull force analysis

Maximum holding power of the magnet – what it depends on?

Magnet power is the result of a measurement for the most favorable conditions, including:

on a plate made of mild steel, effectively closing the magnetic flux
possessing a thickness of at least 10 mm to avoid saturation
characterized by even structure
under conditions of no distance (surface-to-surface)
during pulling in a direction perpendicular to the mounting surface
in stable room temperature

Practical lifting capacity: influencing factors

During everyday use, the real power is determined by a number of factors, ranked from most significant:

Space between magnet and steel – every millimeter of separation (caused e.g. by varnish or unevenness) diminishes the pulling force, often by half at just 0.5 mm.
Direction of force – highest force is available only during pulling at a 90° angle. The shear force of the magnet along the surface is typically many times smaller (approx. 1/5 of the lifting capacity).
Base massiveness – too thin plate does not close the flux, causing part of the power to be lost to the other side.
Steel grade – ideal substrate is pure iron steel. Cast iron may have worse magnetic properties.
Surface quality – the smoother and more polished the plate, the larger the contact zone and higher the lifting capacity. Unevenness creates an air distance.
Temperature influence – high temperature reduces pulling force. Too high temperature can permanently demagnetize the magnet.

Lifting capacity testing was carried out on plates with a smooth surface of optimal thickness, under a perpendicular pulling force, however under shearing force the load capacity is reduced by as much as 5 times. In addition, even a slight gap between the magnet and the plate lowers the load capacity.

Warnings

Medical implants

For implant holders: Strong magnetic fields disrupt electronics. Maintain minimum 30 cm distance or ask another person to handle the magnets.

Thermal limits

Keep cool. NdFeB magnets are susceptible to temperature. If you require operation above 80°C, ask us about special high-temperature series (H, SH, UH).

Combustion hazard

Dust generated during grinding of magnets is flammable. Do not drill into magnets without proper cooling and knowledge.

Threat to electronics

Very strong magnetic fields can corrupt files on payment cards, hard drives, and other magnetic media. Maintain a gap of min. 10 cm.

Do not underestimate power

Exercise caution. Rare earth magnets act from a long distance and snap with massive power, often faster than you can react.

GPS and phone interference

GPS units and smartphones are highly susceptible to magnetism. Direct contact with a powerful NdFeB magnet can decalibrate the internal compass in your phone.

Choking Hazard

These products are not toys. Swallowing multiple magnets can lead to them attracting across intestines, which constitutes a severe health hazard and necessitates immediate surgery.

Beware of splinters

Beware of splinters. Magnets can fracture upon uncontrolled impact, ejecting shards into the air. Wear goggles.

Sensitization to coating

Certain individuals have a sensitization to Ni, which is the standard coating for NdFeB magnets. Frequent touching might lead to a rash. It is best to use safety gloves.

Crushing force

Mind your fingers. Two large magnets will snap together instantly with a force of several hundred kilograms, crushing everything in their path. Exercise extreme caution!

Attention! Details about hazards in the article: Safety of working with magnets.

MP 40x10.4/5.5x5 / N38 - ring magnet

Detailed specification - MP 40x10.4/5.5x5 / N38 - ring magnet

Magnetic properties of material N38

Physical properties of sintered neodymium magnets Nd2Fe14B at 20°C

Engineering simulation of the assembly - data

Table 1: Static force (force vs distance) - characteristics MP 40x10.4/5.5x5 / N38

Table 2: Vertical hold (vertical surface) MP 40x10.4/5.5x5 / N38

Table 3: Wall mounting (shearing) - vertical pull MP 40x10.4/5.5x5 / N38

Table 4: Material efficiency (substrate influence) - sheet metal selection MP 40x10.4/5.5x5 / N38

Table 5: Thermal resistance (stability) - thermal limit MP 40x10.4/5.5x5 / N38

Table 6: Magnet-Magnet interaction (repulsion) - field collision MP 40x10.4/5.5x5 / N38

Table 7: Protective zones (implants) - precautionary measures MP 40x10.4/5.5x5 / N38

Table 8: Dynamics (kinetic energy) - warning MP 40x10.4/5.5x5 / N38

Table 9: Coating parameters (durability) MP 40x10.4/5.5x5 / N38

Table 10: Construction data (Flux) MP 40x10.4/5.5x5 / N38

Table 11: Physics of underwater searching MP 40x10.4/5.5x5 / N38

1. Wall mount (shear)

2. Steel saturation

3. Power loss vs temp

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

Chemical composition

Sustainability

Pulling force

Magnetic Field

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SMZR 25x225 / N52 - magnetic separator with handle

Strengths and weaknesses of neodymium magnets.

Advantages

Disadvantages

Pull force analysis

Maximum holding power of the magnet – what it depends on?

Practical lifting capacity: influencing factors

Warnings

Medical implants

Thermal limits

Combustion hazard

Threat to electronics

Do not underestimate power

GPS and phone interference

Choking Hazard

Beware of splinters

Sensitization to coating

Crushing force

Physical properties of sintered neodymium magnets Nd₂Fe₁₄B at 20°C

Table 1: Static force (force vs distance) - characteristics
MP 40x10.4/5.5x5 / N38

Table 2: Vertical hold (vertical surface)
MP 40x10.4/5.5x5 / N38

Table 3: Wall mounting (shearing) - vertical pull
MP 40x10.4/5.5x5 / N38

Table 4: Material efficiency (substrate influence) - sheet metal selection
MP 40x10.4/5.5x5 / N38

Table 5: Thermal resistance (stability) - thermal limit
MP 40x10.4/5.5x5 / N38

Table 6: Magnet-Magnet interaction (repulsion) - field collision
MP 40x10.4/5.5x5 / N38

Table 7: Protective zones (implants) - precautionary measures
MP 40x10.4/5.5x5 / N38

Table 8: Dynamics (kinetic energy) - warning
MP 40x10.4/5.5x5 / N38

Table 9: Coating parameters (durability)
MP 40x10.4/5.5x5 / N38

Table 10: Construction data (Flux)
MP 40x10.4/5.5x5 / N38

Table 11: Physics of underwater searching
MP 40x10.4/5.5x5 / N38