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MP 40x20x5 / N38 - ring magnet

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

ring magnet

Catalog no 030199

GTIN/EAN: 5906301812166

5.00

Diameter

40 mm [±0,1 mm]

internal diameter Ø

20 mm [±0,1 mm]

Height

5 mm [±0,1 mm]

Weight

35.34 g

Magnetization Direction

↑ axial

Load capacity

7.24 kg / 70.98 N

Magnetic Induction

150.36 mT / 1504 Gs

Coating

[NiCuNi] Nickel

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Technical details - MP 40x20x5 / N38 - ring magnet

Specification / characteristics - MP 40x20x5 / N38 - ring magnet

properties

properties	values
Cat. no.	030199
GTIN/EAN	5906301812166
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	20 mm [±0,1 mm]
Height	5 mm [±0,1 mm]
Weight	35.34 g
Magnetization Direction	↑ axial
Load capacity ~ ?	7.24 kg / 70.98 N
Magnetic Induction ~ ?	150.36 mT / 1504 Gs
Coating	[NiCuNi] Nickel
Manufacturing Tolerance	±0.1 mm

Magnetic properties of material N38

Specification / characteristics MP 40x20x5 / 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 - data

Presented information are the outcome of a engineering calculation. Results rely on models for the material Nd₂Fe₁₄B. Operational performance may differ from theoretical values. Use these data as a preliminary roadmap during assembly planning.

Table 1: Static force (force vs gap) - power drop
MP 40x20x5 / N38

Distance (mm)	Induction (Gauss) / mT	Pull Force (kg/lbs/g/N)	Risk Status
0 mm	5269 Gs 526.9 mT	7.24 kg / 15.96 lbs 7240.0 g / 71.0 N	warning
1 mm	5005 Gs 500.5 mT	6.53 kg / 14.41 lbs 6534.7 g / 64.1 N	warning
2 mm	4739 Gs 473.9 mT	5.86 kg / 12.91 lbs 5857.7 g / 57.5 N	warning
3 mm	4475 Gs 447.5 mT	5.22 kg / 11.51 lbs 5222.2 g / 51.2 N	warning
5 mm	3960 Gs 396.0 mT	4.09 kg / 9.02 lbs 4090.8 g / 40.1 N	warning
10 mm	2832 Gs 283.2 mT	2.09 kg / 4.61 lbs 2092.3 g / 20.5 N	warning
15 mm	1990 Gs 199.0 mT	1.03 kg / 2.28 lbs 1033.4 g / 10.1 N	safe
20 mm	1407 Gs 140.7 mT	0.52 kg / 1.14 lbs 516.3 g / 5.1 N	safe
30 mm	745 Gs 74.5 mT	0.14 kg / 0.32 lbs 144.6 g / 1.4 N	safe
50 mm	268 Gs 26.8 mT	0.02 kg / 0.04 lbs 18.7 g / 0.2 N	safe

Grip strength weakens sharply per each millimeter of gap. Keep in mind that even the smallest gap (e.g., contamination, paint, dust) noticeably weakens the grip. Neodymiums work most effectively during direct contact; gap weakens the force. Notice how flashily the pull force fall, when the magnet does not touch flatly to the steel surface. When calculating the mounting, eliminate redundant distances.

Table 2: Vertical hold (vertical surface)
MP 40x20x5 / N38

Distance (mm)	Friction coefficient	Pull Force (kg/lbs/g/N)
0 mm	Stal (~0.2)	1.45 kg / 3.19 lbs 1448.0 g / 14.2 N
1 mm	Stal (~0.2)	1.31 kg / 2.88 lbs 1306.0 g / 12.8 N
2 mm	Stal (~0.2)	1.17 kg / 2.58 lbs 1172.0 g / 11.5 N
3 mm	Stal (~0.2)	1.04 kg / 2.30 lbs 1044.0 g / 10.2 N
5 mm	Stal (~0.2)	0.82 kg / 1.80 lbs 818.0 g / 8.0 N
10 mm	Stal (~0.2)	0.42 kg / 0.92 lbs 418.0 g / 4.1 N
15 mm	Stal (~0.2)	0.21 kg / 0.45 lbs 206.0 g / 2.0 N
20 mm	Stal (~0.2)	0.10 kg / 0.23 lbs 104.0 g / 1.0 N
30 mm	Stal (~0.2)	0.03 kg / 0.06 lbs 28.0 g / 0.3 N
50 mm	Stal (~0.2)	0.00 kg / 0.01 lbs 4.0 g / 0.0 N

The table below defines the approximate weight limit needed to cause the downward movement of the magnet downwards against a upright steel wall (assuming standard friction). The holding force depends on the separation distance between the magnet and the surface.

Table 3: Wall mounting (shearing) - behavior on slippery surfaces
MP 40x20x5 / N38

Surface type	Friction coefficient / % Mocy	Max load (kg/lbs/g/N)
Raw steel	µ = 0.3 30% Nominalnej Siły	2.17 kg / 4.79 lbs 2172.0 g / 21.3 N
Painted steel (standard)	µ = 0.2 20% Nominalnej Siły	1.45 kg / 3.19 lbs 1448.0 g / 14.2 N
Oily/slippery steel	µ = 0.1 10% Nominalnej Siły	0.72 kg / 1.60 lbs 724.0 g / 7.1 N
Magnet with anti-slip rubber	µ = 0.5 50% Nominalnej Siły	3.62 kg / 7.98 lbs 3620.0 g / 35.5 N

When hanging a element on a vertical wall (e.g., a fridge), it you can count on barely about 1/5 of its nominal power. Gravitational force and a low friction coefficient mean that holders slide down faster than they detach. Planning a vertical fastening? Note that the sliding force is significantly lower than the maximum static pull force. On a smooth steel, the magnet will give way down under a significantly smaller weight. Application of an anti-slip coating can drastically increase the grip.

Table 4: Material efficiency (substrate influence) - power losses
MP 40x20x5 / N38

Steel thickness (mm)	% power	Real pull force (kg/lbs/g/N)
0.5 mm	10%	0.72 kg / 1.60 lbs 724.0 g / 7.1 N
1 mm	25%	1.81 kg / 3.99 lbs 1810.0 g / 17.8 N
2 mm	50%	3.62 kg / 7.98 lbs 3620.0 g / 35.5 N
3 mm	75%	5.43 kg / 11.97 lbs 5430.0 g / 53.3 N
5 mm	100%	7.24 kg / 15.96 lbs 7240.0 g / 71.0 N
10 mm	100%	7.24 kg / 15.96 lbs 7240.0 g / 71.0 N
11 mm	100%	7.24 kg / 15.96 lbs 7240.0 g / 71.0 N
12 mm	100%	7.24 kg / 15.96 lbs 7240.0 g / 71.0 N

A thin metal plate is not enough to take in the full magnetic flux, which weakens actual performance of the holder. If you mount a strong magnet to a thin surface, the magnetism will pass right through and the holding will be smaller. To squeeze 100% of this magnet's potential, you require a sufficiently solid backing of steel. The material oversaturation means that on sheet metal structures (e.g., car bodies), the holder works worse. We suggest choosing the steel cross-section from these parameters.

Table 5: Thermal resistance (stability) - power drop
MP 40x20x5 / N38

Ambient temp. (°C)	Power loss	Remaining pull (kg/lbs/g/N)	Status
20 °C	0.0%	7.24 kg / 15.96 lbs 7240.0 g / 71.0 N	OK
40 °C	-2.2%	7.08 kg / 15.61 lbs 7080.7 g / 69.5 N	OK
60 °C	-4.4%	6.92 kg / 15.26 lbs 6921.4 g / 67.9 N	OK
80 °C	-6.6%	6.76 kg / 14.91 lbs 6762.2 g / 66.3 N
100 °C	-28.8%	5.15 kg / 11.36 lbs 5154.9 g / 50.6 N

Ordinary NdFeB products irreversibly lose strength above the temperature limit. Protect against heat – heat can permanently destroy this magnet. With every degree above norm, the neodymium's capacity briefly drops. Avoid using this magnet near heat sources higher than its safe range. Ignoring the limit will result in destruction of magnetism.

*Engineering note: Thermal stability depends not only on the material grade, but also on the magnet's shape. Flat magnets (pancake types) risk losing magnetic properties sooner than long magnets. The danger warning in the table signals permanent field degradation for this particular item.

Table 6: Magnet-Magnet interaction (repulsion) - field range
MP 40x20x5 / N38

Gap (mm)	Attraction (kg/lbs) (N-S)	Shear Strength (kg/lbs/g/N)	Repulsion (kg/lbs) (N-N)
0 mm	179.94 kg / 396.69 lbs 5 920 Gs	26.99 kg / 59.50 lbs 26991 g / 264.8 N	N/A
1 mm	171.16 kg / 377.35 lbs 10 277 Gs	25.67 kg / 56.60 lbs 25675 g / 251.9 N	154.05 kg / 339.62 lbs ~0 Gs
2 mm	162.41 kg / 358.05 lbs 10 011 Gs	24.36 kg / 53.71 lbs 24361 g / 239.0 N	146.17 kg / 322.24 lbs ~0 Gs
3 mm	153.87 kg / 339.24 lbs 9 744 Gs	23.08 kg / 50.89 lbs 23081 g / 226.4 N	138.49 kg / 305.31 lbs ~0 Gs
5 mm	137.55 kg / 303.25 lbs 9 213 Gs	20.63 kg / 45.49 lbs 20633 g / 202.4 N	123.80 kg / 272.92 lbs ~0 Gs
10 mm	101.67 kg / 224.14 lbs 7 921 Gs	15.25 kg / 33.62 lbs 15251 g / 149.6 N	91.50 kg / 201.73 lbs ~0 Gs
20 mm	52.00 kg / 114.64 lbs 5 665 Gs	7.80 kg / 17.20 lbs 7800 g / 76.5 N	46.80 kg / 103.18 lbs ~0 Gs
50 mm	6.64 kg / 14.64 lbs 2 025 Gs	1.00 kg / 2.20 lbs 996 g / 9.8 N	5.98 kg / 13.18 lbs ~0 Gs
60 mm	3.59 kg / 7.92 lbs 1 489 Gs	0.54 kg / 1.19 lbs 539 g / 5.3 N	3.23 kg / 7.13 lbs ~0 Gs
70 mm	2.03 kg / 4.48 lbs 1 120 Gs	0.30 kg / 0.67 lbs 305 g / 3.0 N	1.83 kg / 4.03 lbs ~0 Gs
80 mm	1.20 kg / 2.64 lbs 860 Gs	0.18 kg / 0.40 lbs 180 g / 1.8 N	1.08 kg / 2.38 lbs ~0 Gs
90 mm	0.73 kg / 1.62 lbs 673 Gs	0.11 kg / 0.24 lbs 110 g / 1.1 N	0.66 kg / 1.46 lbs ~0 Gs
100 mm	0.47 kg / 1.03 lbs 536 Gs	0.07 kg / 0.15 lbs 70 g / 0.7 N	0.42 kg / 0.92 lbs ~0 Gs

Two magnets attract each other from a wider radius than a neodymium and metal combination. The connection of magnet-to-magnet produces a massive flux and a further horizon of operation. Want to build a strong closure? Apply two magnets instead of a neodymium and a steel. Be careful that when attracting two neodymiums, the impact force is massive. The levitation is marginally weaker than the connection force, but still impressive.
*The magnetic induction between like poles reaches ~0 Gs in the exact middle of the gap (caused by magnetic field nullification).
Attention: Estimates demonstrate friction force of two identical neodymium magnets (friction ~0.15 for Ni-Ni layer).

Table 7: Protective zones (implants) - warnings
MP 40x20x5 / N38

Object / Device	Limit (Gauss) / mT	Safe distance
Pacemaker	5 Gs (0.5 mT)	24.0 cm
Hearing aid	10 Gs (1.0 mT)	18.5 cm
Timepiece	20 Gs (2.0 mT)	14.5 cm
Mobile device	40 Gs (4.0 mT)	11.0 cm
Car key	50 Gs (5.0 mT)	10.5 cm
Payment card	400 Gs (40.0 mT)	4.5 cm
HDD hard drive	600 Gs (60.0 mT)	3.5 cm

A strong magnetic field is a real danger to electronics and pacemakers. These magnets produce a field that prevents correct functioning of sensitive medical devices. Be aware: the invisible magnetic field passes through tissues and plastic. Increased vigilance must be taken by people with cochlear implants and drug dispensers. Influence will be felt by: mechanical watches, remotes, speakers, and displays. Do not place the magnet near cards, HDD media, or sensitive navigation tools.

Table 8: Dynamics (kinetic energy) - warning
MP 40x20x5 / N38

Start from (mm)	Speed (km/h)	Energy (J)
10 mm	16.84 km/h (4.68 m/s)	0.39 J
30 mm	25.31 km/h (7.03 m/s)	0.87 J
50 mm	32.33 km/h (8.98 m/s)	1.43 J
100 mm	45.65 km/h (12.68 m/s)	2.84 J

Magnetic elements are prone to chipping – a violent impact against metal causes immediate chipping. Watch the impact speed – a neodymium left loose speeds with massive force. Striking energy can cause material chips or painful pinches to skin. Be sure to control the product during mounting so it doesn't hit violently against the steel surface. A collision at high speed almost guarantees destruction of the neodymium. Use safety goggles when playing with powerful specimens.

Table 9: Coating parameters (durability)
MP 40x20x5 / N38

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

The SST (salt spray test) is an industry standard for determining coating lifespan in harsh conditions. Note the thickness of the protective layer.

Table 10: Construction data (P_c)
MP 40x20x5 / N38

Parameter	Value	SI Unit / Description
Magnetic Flux	56 325 Mx	563.3 µWb
P_c Coefficient	0.80	High (Stable)

Total magnetic flux passing through the pole surface. Essential parameter when building generators and motors. P_c value determines the working geometry.

Table 11: Hydrostatics and buoyancy
MP 40x20x5 / N38

Environment	Effective steel pull	Effect
Air (land)	7.24 kg	Standard
Water (riverbed)	8.29 kg (+1.05 kg buoyancy gain)	+14.5%

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

Contrary to myths, water does not block the magnetic field. However, remember the water resistance when pulling the rope quickly.

1. Vertical hold

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

2. Steel saturation

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

3. Power loss vs temp

*For standard magnets, 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) = 0.80

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: 030199-2026

Measurement Calculator

Force (pull)

lbs

Magnetic Induction

Gauss (Gs)

Type data in one of the inputs, and the rest convert automatically.

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The ring-shaped magnet MP 40x20x5 / N38 is created for mechanical fastening, 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. 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 40x20x5 / N38. Neodymium magnets are sintered ceramics, which means they are hard but breakable and inelastic. When tightening the screw, you must maintain caution. We recommend tightening manually with a screwdriver, not an impact driver, because excessive force will cause the ring to crack. The flat screw head should evenly press the magnet. Remember: cracking during assembly results from material properties, not a product defect.

These magnets are coated with standard Ni-Cu-Ni plating, which protects them in indoor conditions, but does not ensure full waterproofing. 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.

A screw or bolt with a thread diameter smaller than 20 mm fits this model. 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.

The presented product is a ring magnet with dimensions Ø40 mm (outer diameter) and height 5 mm. The pulling force of this model is an impressive 7.24 kg, which translates to 70.98 N in newtons. The mounting hole diameter is precisely 20 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.

Pros and cons of neodymium magnets.

Pros

Apart from their consistent holding force, neodymium magnets have these key benefits:

Their magnetic field is durable, and after approximately 10 years it decreases only by ~1% (theoretically),
They possess excellent resistance to magnetic field loss when exposed to opposing magnetic fields,
In other words, due to the metallic finish of silver, the element is aesthetically pleasing,
The surface of neodymium magnets generates a intense magnetic field – this is one of their assets,
Thanks to resistance to high temperature, they are able to function (depending on the form) even at temperatures up to 230°C and higher...
Possibility of custom modeling as well as adjusting to individual conditions,
Huge importance in high-tech industry – they find application in magnetic memories, electric motors, advanced medical instruments, and multitasking production systems.
Thanks to concentrated force, small magnets offer high operating force, occupying minimum space,

Weaknesses

Disadvantages of neodymium magnets:

Brittleness is one of their disadvantages. Upon intense impact they can fracture. We advise keeping them in a strong case, which not only secures them against impacts but also raises their durability
When exposed to high temperature, neodymium magnets experience a drop in power. Often, when the temperature exceeds 80°C, their power decreases (depending on the size, as well as shape of the magnet). For those who need magnets for extreme conditions, we offer [AH] versions withstanding up to 230°C
When exposed to humidity, magnets usually rust. For applications outside, it is recommended to use protective magnets, such as those in rubber or plastics, which secure oxidation and corrosion.
We recommend cover - magnetic holder, due to difficulties in producing threads inside the magnet and complicated forms.
Health risk related to microscopic parts of magnets can be dangerous, in case of ingestion, which gains importance in the context of child health protection. It is also worth noting that small components of these devices can be problematic in diagnostics medical after entering the body.
With budget limitations the cost of neodymium magnets is a challenge,

Pull force analysis

Best holding force of the magnet in ideal parameters – what it depends on?

The force parameter is a result of laboratory testing performed under the following configuration:

using a plate made of mild steel, functioning as a magnetic yoke
whose transverse dimension equals approx. 10 mm
characterized by even structure
under conditions of ideal adhesion (metal-to-metal)
during pulling in a direction vertical to the plane
at standard ambient temperature

Lifting capacity in real conditions – factors

Please note that the application force will differ subject to the following factors, in order of importance:

Gap between surfaces – every millimeter of distance (caused e.g. by varnish or unevenness) significantly weakens the pulling force, often by half at just 0.5 mm.
Load vector – maximum parameter is obtained only during perpendicular pulling. The force required to slide of the magnet along the surface is typically several times lower (approx. 1/5 of the lifting capacity).
Base massiveness – too thin plate does not accept the full field, causing part of the flux to be escaped into the air.
Chemical composition of the base – mild steel attracts best. Alloy steels reduce magnetic properties and holding force.
Surface finish – ideal contact is possible only on polished steel. Any scratches and bumps create air cushions, weakening the magnet.
Thermal environment – temperature increase causes a temporary drop of force. Check the maximum operating temperature for a given model.

Lifting capacity was measured with the use of a steel plate with a smooth surface of optimal thickness (min. 20 mm), under perpendicular detachment force, whereas under shearing force the lifting capacity is smaller. Additionally, even a small distance between the magnet and the plate lowers the load capacity.

H&S for magnets

Compass and GPS

An intense magnetic field interferes with the functioning of magnetometers in phones and GPS navigation. Maintain magnets near a device to avoid breaking the sensors.

Fire risk

Drilling and cutting of neodymium magnets poses a fire hazard. Neodymium dust reacts violently with oxygen and is difficult to extinguish.

Adults only

Strictly store magnets out of reach of children. Risk of swallowing is high, and the consequences of magnets clamping inside the body are tragic.

Data carriers

Very strong magnetic fields can corrupt files on credit cards, HDDs, and storage devices. Stay away of min. 10 cm.

Eye protection

Despite metallic appearance, the material is brittle and cannot withstand shocks. Do not hit, as the magnet may crumble into hazardous fragments.

Operating temperature

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

Metal Allergy

Some people experience a hypersensitivity to Ni, which is the common plating for NdFeB magnets. Extended handling may cause skin redness. We recommend use safety gloves.

Respect the power

Exercise caution. Rare earth magnets attract from a long distance and connect with huge force, often faster than you can move away.

Crushing force

Large magnets can crush fingers in a fraction of a second. Never put your hand betwixt two attracting surfaces.

Health Danger

Warning for patients: Strong magnetic fields affect electronics. Maintain at least 30 cm distance or request help to work with the magnets.

Danger! Need more info? Check our post: Why are neodymium magnets dangerous?

MP 40x20x5 / N38 - ring magnet

Technical details - MP 40x20x5 / N38 - ring magnet

Magnetic properties of material N38

Physical properties of sintered neodymium magnets Nd2Fe14B at 20°C

Physical analysis of the assembly - data

Table 1: Static force (force vs gap) - power drop MP 40x20x5 / N38

Table 2: Vertical hold (vertical surface) MP 40x20x5 / N38

Table 3: Wall mounting (shearing) - behavior on slippery surfaces MP 40x20x5 / N38

Table 4: Material efficiency (substrate influence) - power losses MP 40x20x5 / N38

Table 5: Thermal resistance (stability) - power drop MP 40x20x5 / N38

Table 6: Magnet-Magnet interaction (repulsion) - field range MP 40x20x5 / N38

Table 7: Protective zones (implants) - warnings MP 40x20x5 / N38

Table 8: Dynamics (kinetic energy) - warning MP 40x20x5 / N38

Table 9: Coating parameters (durability) MP 40x20x5 / N38

Table 10: Construction data (Pc) MP 40x20x5 / N38

Table 11: Hydrostatics and buoyancy MP 40x20x5 / N38

1. Vertical hold

2. Steel saturation

3. Power loss vs temp

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

Material specification

Ecology and recycling (GPSR)

Force (pull)

Magnetic Induction

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Pros and cons of neodymium magnets.

Pros

Weaknesses

Pull force analysis

Best holding force of the magnet in ideal parameters – what it depends on?

Lifting capacity in real conditions – factors

H&S for magnets

Compass and GPS

Fire risk

Adults only

Data carriers

Eye protection

Operating temperature

Metal Allergy

Respect the power

Crushing force

Health Danger

Physical properties of sintered neodymium magnets Nd₂Fe₁₄B at 20°C

Table 1: Static force (force vs gap) - power drop
MP 40x20x5 / N38

Table 2: Vertical hold (vertical surface)
MP 40x20x5 / N38

Table 3: Wall mounting (shearing) - behavior on slippery surfaces
MP 40x20x5 / N38

Table 4: Material efficiency (substrate influence) - power losses
MP 40x20x5 / N38

Table 5: Thermal resistance (stability) - power drop
MP 40x20x5 / N38

Table 6: Magnet-Magnet interaction (repulsion) - field range
MP 40x20x5 / N38

Table 7: Protective zones (implants) - warnings
MP 40x20x5 / N38

Table 8: Dynamics (kinetic energy) - warning
MP 40x20x5 / N38

Table 9: Coating parameters (durability)
MP 40x20x5 / N38

Table 10: Construction data (P_c)
MP 40x20x5 / N38

Table 11: Hydrostatics and buoyancy
MP 40x20x5 / N38