Product available Ships tomorrow

MP 40x20x5 / 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 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

check properties »

12.24 ZŁ with VAT / pcs + price for transport

9.95 ZŁ net + 23% VAT / pcs

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Technical - 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

Technical simulation of the product - report

The following values are the direct effect of a physical calculation. Results were calculated on algorithms for the material Nd₂Fe₁₄B. Actual conditions might slightly differ. Please consider these data as a preliminary roadmap for designers.

Table 1: Static force (pull vs distance) - characteristics
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	weak grip
20 mm	1407 Gs 140.7 mT	0.52 kg / 1.14 lbs 516.3 g / 5.1 N	weak grip
30 mm	745 Gs 74.5 mT	0.14 kg / 0.32 lbs 144.6 g / 1.4 N	weak grip
50 mm	268 Gs 26.8 mT	0.02 kg / 0.04 lbs 18.7 g / 0.2 N	weak grip

Magnetic force weakens significantly per each millimeter of spacing. Note that even the smallest gap (e.g., dirt, paint, rust) significantly reduces the pull force. Magnets operate optimally at the point of direct contact; gap weakens the power. See how flashily the parameters drop, when the magnet does not touch directly to the metal substrate. When planning the arrangement, avoid redundant distances.

Table 2: Sliding 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 following data indicates the estimated weight limit required to initiate the shifting of the magnet down on a vertical metal surface (considering typical friction coefficient). This value varies with the gap size between the magnet and the metal.

Table 3: Wall mounting (sliding) - 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 mounting a element on a vertical plane (e.g., a fridge), it will maintain just about 20%-30% of nominal attraction strength. Gravity as well as a weak degree of grip cause that products slide down faster than they pop off the substrate. Designing a wall mount? Remember that the shear force is significantly lower than the maximum static pull force. On a painted metal, the magnet will slip down under a much lighter cargo. Application of an anti-slip coating can drastically increase the grip.

Table 4: Material efficiency (saturation) - 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 sheet is unable to absorb the full magnetic flux, which squanders power of the magnet. If you install a neodymium to a too thin substrate, the flux will pass right through and the holding will be smaller. To utilize the maximum of this neodymium's potential, you require a sufficiently solid piece of steel. The saturation phenomenon causes that on sheet metal structures (e.g., car bodies), the product holds weaker. We recommend selecting the steel thickness from these parameters.

Table 5: Working in heat (material behavior) - thermal limit
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

Standard neodymium magnets irreversibly lose power above the temperature limit. Avoid high temperatures – heat can irreversibly demagnetize this magnet. As the temperature rises, the magnet's power momentarily drops. Do not use this product close to heaters exceeding its safe range. Exceeding the critical threshold will lead to destruction of magnetism.

*Engineering note: Thermal stability is determined by both grade, but also on the magnet's shape. Thin magnets (pancake types) risk losing magnetic properties sooner than taller cylinders. Red status in the table signals a risk of irreversible loss for this particular item.

Table 6: Two magnets (attraction) - forces in the system
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 interact from a significantly greater distance than a magnet and sheet setup. The connection of magnet-to-magnet produces a massive flux and a wider radius of performance. Want to build a strong closure? Use a pair of magnets instead of one magnet and a striker plate. Be careful that when attracting two neodymiums, the impact force is massive. The repulsion force is a bit weaker than the attraction, but still impressive.
*The magnetic induction in repulsion mode reaches ~0 Gs at the midpoint between the magnets (resulting from vector opposition).
* Calculations apply to sliding force of dual same 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
Mechanical watch	20 Gs (2.0 mT)	14.5 cm
Phone / Smartphone	40 Gs (4.0 mT)	11.0 cm
Remote	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

Extremely neodym field is a serious hazard to electronics and pacemakers. These neodymiums produce a field that disrupts operation of sensitive medical devices. Notice: the invisible magnetic field acts through matter and plastic. Exceptional care must be exercised by people with hearing aids and insulin pumps. Also at risk are: automatic timepieces, car keys, speakers, and displays. Do not place the magnet near cards, hard drives, or precise measuring instruments.

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

Neodymium magnets are delicate – a strong collision with metal risks their cracking. Control the attraction moment – a magnet released freely speeds with massive force. Kinetic force can cause material chips or painful pinches to fingers. Be sure to control the product during mounting so it doesn't hit violently against the metal. A collision at high speed means shattering of the neodymium. Use safety goggles when working with large magnets.

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)

Neodymium magnets are highly susceptible to corrosion without proper protection. The silver nickel coating also serves an aesthetic function but is not fully waterproof.

Table 10: Electrical data (Flux)
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 for generator designers and motors. The P_c coefficient determines the working geometry.

Table 11: Physics of underwater searching
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%

Rust risk: Remember to wipe the magnet thoroughly after removing it from water and apply a protective layer (e.g., oil) to avoid corrosion.

The magnetic field penetrates through water without any losses. As a result, your magnet will pull a heavier object from the bottom than if you lifted it in the air.

1. Shear force

*Caution: On a vertical surface, the magnet holds just ~20% of its nominal pull.

2. Steel saturation

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

3. Heat tolerance

*For N38 material, the safety limit is 80°C.

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

chart generated for the permeance coefficient P_c (Permeance Coefficient) = 0.80

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

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%

Environmental data

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

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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 material behaves more like porcelain than steel, so it doesn't forgive mistakes during mounting. 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.

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 indoor use. For outdoor applications, we recommend choosing magnets in hermetic housing or additional protection with varnish.

The inner hole diameter determines the maximum size of the mounting element. For magnets with a straight hole, a conical head can act like a wedge and burst the magnet. Aesthetic mounting requires selecting the appropriate head size.

This model is characterized by dimensions Ø40x5 mm and a weight of 35.34 g. The pulling force of this model is an impressive 7.24 kg, which translates to 70.98 N in newtons. The product has a [NiCuNi] coating and is made of NdFeB material. Inner hole dimension: 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 as well as cons of Nd₂Fe₁₄B magnets.

Benefits

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

They retain magnetic properties for almost ten years – the loss is just ~1% (based on simulations),
They are resistant to demagnetization induced by external disturbances,
By using a lustrous coating of gold, the element has an elegant look,
Magnets exhibit huge magnetic induction on the working surface,
Through (appropriate) combination of ingredients, they can achieve high thermal resistance, allowing for functioning at temperatures reaching 230°C and above...
Thanks to versatility in constructing and the capacity to customize to individual projects,
Significant place in high-tech industry – they find application in computer drives, electromotive mechanisms, diagnostic systems, also multitasking production systems.
Relatively small size with high pulling force – neodymium magnets offer high power in tiny dimensions, which makes them useful in compact constructions

Limitations

Disadvantages of neodymium magnets:

To avoid cracks upon strong impacts, we recommend using special steel housings. Such a solution protects the magnet and simultaneously increases its durability.
Neodymium magnets lose force when exposed to high temperatures. After reaching 80°C, many of them experience permanent weakening of strength (a factor is the shape and 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
Magnets exposed to a humid environment can corrode. Therefore while using outdoors, we recommend using water-impermeable magnets made of rubber, plastic or other material resistant to moisture
Limited possibility of creating threads in the magnet and complicated forms - preferred is cover - magnet mounting.
Possible danger to health – tiny shards of magnets are risky, when accidentally swallowed, which gains importance in the context of child safety. It is also worth noting that tiny parts of these magnets are able to complicate diagnosis medical when they are in the body.
High unit price – neodymium magnets cost more than other types of magnets (e.g. ferrite), which can limit application in large quantities

Holding force characteristics

Detachment force of the magnet in optimal conditions – what affects it?

The force parameter is a measurement result executed under standard conditions:

with the application of a yoke made of low-carbon steel, guaranteeing maximum field concentration
with a cross-section minimum 10 mm
characterized by smoothness
without any air gap between the magnet and steel
for force applied at a right angle (in the magnet axis)
in neutral thermal conditions

Lifting capacity in real conditions – factors

In real-world applications, the actual lifting capacity results from several key aspects, ranked from the most important:

Gap between magnet and steel – every millimeter of distance (caused e.g. by varnish or dirt) significantly weakens the magnet efficiency, often by half at just 0.5 mm.
Loading method – catalog parameter refers to detachment vertically. When applying parallel force, the magnet exhibits much less (often approx. 20-30% of nominal force).
Element thickness – to utilize 100% power, the steel must be adequately massive. Thin sheet restricts the attraction force (the magnet "punches through" it).
Chemical composition of the base – mild steel gives the best results. Alloy steels lower magnetic permeability and lifting capacity.
Smoothness – full contact is possible only on polished steel. Rough texture reduce the real contact area, reducing force.
Heat – neodymium magnets have a negative temperature coefficient. When it is hot they lose power, and in frost gain strength (up to a certain limit).

Holding force was tested on the plate surface of 20 mm thickness, when the force acted perpendicularly, whereas under shearing force the lifting capacity is smaller. In addition, even a slight gap between the magnet and the plate reduces the lifting capacity.

H&S for magnets

Serious injuries

Danger of trauma: The pulling power is so immense that it can result in blood blisters, pinching, and even bone fractures. Protective gloves are recommended.

Dust explosion hazard

Combustion risk: Rare earth powder is explosive. Do not process magnets without safety gear as this risks ignition.

GPS and phone interference

Navigation devices and smartphones are extremely susceptible to magnetism. Direct contact with a powerful NdFeB magnet can decalibrate the sensors in your phone.

Danger to the youngest

Product intended for adults. Small elements pose a choking risk, leading to intestinal necrosis. Keep out of reach of children and animals.

Do not overheat magnets

Do not overheat. NdFeB magnets are susceptible to temperature. If you require resistance above 80°C, ask us about HT versions (H, SH, UH).

Respect the power

Handle with care. Neodymium magnets act from a distance and snap with huge force, often quicker than you can move away.

Warning for heart patients

Patients with a pacemaker have to maintain an large gap from magnets. The magnetic field can interfere with the operation of the implant.

Magnet fragility

NdFeB magnets are sintered ceramics, which means they are fragile like glass. Collision of two magnets will cause them breaking into small pieces.

Threat to electronics

Do not bring magnets close to a wallet, laptop, or TV. The magnetism can destroy these devices and wipe information from cards.

Nickel allergy

Medical facts indicate that the nickel plating (the usual finish) is a strong allergen. For allergy sufferers, avoid touching magnets with bare hands or select versions in plastic housing.

Attention! More info about hazards in the article: Magnet Safety Guide.

MP 40x20x5 / N38 - ring magnet

Technical - MP 40x20x5 / N38 - ring magnet

Magnetic properties of material N38

Physical properties of sintered neodymium magnets Nd2Fe14B at 20°C

Technical simulation of the product - report

Table 1: Static force (pull vs distance) - characteristics MP 40x20x5 / N38

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

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

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

Table 5: Working in heat (material behavior) - thermal limit MP 40x20x5 / N38

Table 6: Two magnets (attraction) - forces in the system 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: Electrical data (Flux) MP 40x20x5 / N38

Table 11: Physics of underwater searching MP 40x20x5 / N38

1. Shear force

2. Steel saturation

3. Heat tolerance

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

Material specification

Environmental data

Magnet pull force

Field Strength

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Pros as well as cons of Nd2Fe14B magnets.

Benefits

Limitations

Holding force characteristics

Detachment force of the magnet in optimal conditions – what affects it?

Lifting capacity in real conditions – factors

H&S for magnets

Serious injuries

Dust explosion hazard

GPS and phone interference

Danger to the youngest

Do not overheat magnets

Respect the power

Warning for heart patients

Magnet fragility

Threat to electronics

Nickel allergy

Physical properties of sintered neodymium magnets Nd₂Fe₁₄B at 20°C

Table 1: Static force (pull vs distance) - characteristics
MP 40x20x5 / N38

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

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

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

Table 5: Working in heat (material behavior) - thermal limit
MP 40x20x5 / N38

Table 6: Two magnets (attraction) - forces in the system
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: Electrical data (Flux)
MP 40x20x5 / N38

Table 11: Physics of underwater searching
MP 40x20x5 / N38

Pros as well as cons of Nd₂Fe₁₄B magnets.