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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

technical specifications »

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Detailed specification - 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

Engineering modeling of the magnet - data

The following data are the outcome of a mathematical calculation. Results rely on algorithms for the material Nd₂Fe₁₄B. Actual performance may deviate from the simulation results. Treat these data as a preliminary roadmap when designing systems.

Table 1: Static force (force vs gap) - interaction chart
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	low risk
20 mm	1407 Gs 140.7 mT	0.52 kg / 1.14 lbs 516.3 g / 5.1 N	low risk
30 mm	745 Gs 74.5 mT	0.14 kg / 0.32 lbs 144.6 g / 1.4 N	low risk
50 mm	268 Gs 26.8 mT	0.02 kg / 0.04 lbs 18.7 g / 0.2 N	low risk

Grip strength decreases drastically with every mm of spacing. Remember that even a microscopic distance (e.g., dirt, varnish, rust) significantly diminishes the holding power. Neodymiums work strongest during direct contact; gap drastically cuts the power. Notice how flashily the load capacity plummet, when the product does not adhere directly to the steel surface. When designing the mounting, avoid unnecessary gaps.

Table 2: Sliding capacity (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

This section shows the theoretical shear load necessary to cause the shifting of the magnet down against a vertical metal surface (assuming standard friction coefficient). This value is a function of the 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 mounting a holder on a upright plane (e.g., a fridge), it will only hold just about 20%-30% of nominal attraction strength. Gravity as well as a low friction coefficient cause that products slip faster than they detach. Want to create a hanger? Note that the shear force is much weaker than the maximum static pull force. On a slippery surface, the holder will slide down under a much lighter cargo. Application of an anti-slip pad can significantly raise the stability.

Table 4: Steel thickness (saturation) - sheet metal selection
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 cannot absorb the full magnetic flux, which weakens actual performance of the holder. Should you mount a strong magnet to a weak sheet, the flux will pass right through and the pull force will drop sharply. To achieve the maximum of this neodymium's potential, you require a sufficiently solid piece of steel. The material oversaturation causes that on thin elements (e.g., appliance housings), the holder shows lower pull force. We recommend selecting the steel cross-section based on the following data.

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

Ordinary NdFeB products lose strength past the thermal threshold. Watch out for overheating – excessive heat can permanently demagnetize this product. As the temperature rises, the neodymium's capacity momentarily lowers. Avoid using this magnet in hot environments exceeding its safe range. Exceeding the critical threshold will cause irreversible degradation of magnetism.

*Important note: Temperature resistance is determined by both grade, but also on the magnet's shape. Low-profile magnets (pancake types) risk losing magnetic properties at lower temperatures than long magnets. The danger warning in the table points to a risk of irreversible loss for this specific geometry.

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

Gap (mm)	Attraction (kg/lbs) (N-S)	Shear Force (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 combination. Such a system of magnet-to-magnet generates a stronger field and a wider radius of operation. Designing a powerful holder? Apply two magnets instead of one magnet and a steel. Be careful that when connecting a pair of magnets, the collision energy is extreme. The levitation is slightly lower than the attraction, but still significant.
*The magnetic induction for N-N configuration reaches ~0 Gs in the exact middle between the magnets (caused by magnetic field nullification).
Important: Calculations apply to shear force of a pair of same 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
Phone / Smartphone	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

Extremely neodym field is a real danger to electronic devices and medical implants. These NdFeB products produce a field that disrupts operation of digital equipment. Notice: the invisible magnetic field penetrates the body and housings. Increased vigilance must be exercised by people with cochlear implants and insulin pumps. Also at risk are: mechanical watches, remotes, membranes, and screens. Do not bring the product near payment cards, hard drives, or precise measuring instruments.

Table 8: Collisions (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

NdFeB products are delicate – a collision with steel risks their cracking. Pay attention to connection velocity – a magnet released freely turns into a projectile. Impact energy can cause material chips or painful pinches to skin. Be sure to control the product during bringing near metal so it doesn't slam with momentum against the metal. A contact at a velocity of dozens of km/h means shattering of the magnet. Wear eye protection when working with large magnets.

Table 9: Surface protection spec
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 following table defines the conditions under which this product can be safely used. Note the thickness of the protective layer.

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)

Flux value emitted by the magnet pole. Essential parameter in coil applications and motors. P_c value defines the working geometry.

Table 11: Submerged application
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: 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. However, remember the water resistance when pulling the rope quickly.

1. Wall mount (shear)

*Note: On a vertical surface, the magnet holds just approx. 20-30% of its max power.

2. Efficiency vs thickness

*Thin metal sheet (e.g. computer case) drastically reduces the holding force.

3. Heat tolerance

*For N38 material, 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

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.

Engineering data and GPSR

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

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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. 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.

These magnets are coated with standard Ni-Cu-Ni plating, which protects them in indoor conditions, but is not sufficient for rain. In the place of the mounting hole, the coating is thinner and can be damaged 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 key parameter here is the holding force amounting to approximately 7.24 kg (force ~70.98 N). The mounting hole diameter is precisely 20 mm.

The poles are located on the planes with holes, not on the sides of the ring. If you want two such magnets screwed with cones facing each other (faces) to attract, you must connect them with opposite poles (N to S). When ordering a larger quantity, magnets are usually packed in stacks, where they are already naturally paired.

Advantages and disadvantages of neodymium magnets.

Strengths

Besides their remarkable field intensity, neodymium magnets offer the following advantages:

They retain full power for nearly ten years – the drop is just ~1% (according to analyses),
They are resistant to demagnetization induced by external magnetic fields,
The use of an shiny finish of noble metals (nickel, gold, silver) causes the element to have aesthetics,
Neodymium magnets deliver maximum magnetic induction on a their surface, which ensures high operational effectiveness,
Neodymium magnets are characterized by extremely high magnetic induction on the magnet surface and are able to act (depending on the form) even at a temperature of 230°C or more...
In view of the option of accurate shaping and adaptation to individualized solutions, neodymium magnets can be modeled in a variety of forms and dimensions, which makes them more universal,
Significant place in innovative solutions – they find application in HDD drives, brushless drives, advanced medical instruments, as well as multitasking production systems.
Thanks to their power density, small magnets offer high operating force, in miniature format,

Limitations

Disadvantages of neodymium magnets:

Brittleness is one of their disadvantages. Upon strong impact they can fracture. We recommend keeping them in a steel housing, which not only protects them against impacts but also raises their durability
Neodymium magnets decrease their force under the influence of heating. As soon as 80°C is exceeded, many of them start losing their power. Therefore, we recommend our special magnets marked [AH], which maintain durability even at temperatures up to 230°C
Due to the susceptibility of magnets to corrosion in a humid environment, we suggest using waterproof magnets made of rubber, plastic or other material stable to moisture, when using outdoors
We suggest a housing - magnetic holder, due to difficulties in producing nuts inside the magnet and complex forms.
Possible danger to health – tiny shards of magnets can be dangerous, when accidentally swallowed, which is particularly important in the context of child health protection. It is also worth noting that small components of these devices are able to disrupt the diagnostic process medical when they are in the body.
Higher cost of purchase is a significant factor to consider compared to ceramic magnets, especially in budget applications

Pull force analysis

Maximum lifting capacity of the magnet – what it depends on?

Information about lifting capacity was determined for ideal contact conditions, including:

on a plate made of mild steel, effectively closing the magnetic field
possessing a thickness of min. 10 mm to avoid saturation
characterized by even structure
with direct contact (without impurities)
for force applied at a right angle (in the magnet axis)
at standard ambient temperature

Determinants of lifting force in real conditions

In real-world applications, the real power results from several key aspects, listed from crucial:

Space between magnet and steel – every millimeter of separation (caused e.g. by varnish or dirt) significantly weakens the magnet efficiency, often by half at just 0.5 mm.
Direction of force – highest force is reached only during pulling at a 90° angle. The resistance to sliding of the magnet along the surface is typically many times smaller (approx. 1/5 of the lifting capacity).
Plate thickness – insufficiently thick steel causes magnetic saturation, causing part of the flux to be wasted into the air.
Steel grade – ideal substrate is pure iron steel. Hardened steels may have worse magnetic properties.
Surface condition – ground elements ensure maximum contact, which increases field saturation. Rough surfaces reduce efficiency.
Temperature – heating the magnet causes a temporary drop of induction. It is worth remembering the thermal limit for a given model.

Lifting capacity was measured with the use of a smooth steel plate of suitable thickness (min. 20 mm), under perpendicular pulling force, however under parallel forces the holding force is lower. In addition, even a small distance between the magnet and the plate reduces the lifting capacity.

Safety rules for work with NdFeB magnets

Powerful field

Before use, check safety instructions. Uncontrolled attraction can break the magnet or injure your hand. Think ahead.

Protect data

Avoid bringing magnets near a purse, laptop, or screen. The magnetic field can permanently damage these devices and wipe information from cards.

Material brittleness

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

Choking Hazard

Always store magnets out of reach of children. Choking hazard is significant, and the effects of magnets clamping inside the body are very dangerous.

Keep away from electronics

A powerful magnetic field negatively affects the functioning of magnetometers in phones and navigation systems. Maintain magnets close to a smartphone to avoid breaking the sensors.

Sensitization to coating

Certain individuals suffer from a sensitization to Ni, which is the common plating for neodymium magnets. Frequent touching may cause dermatitis. We strongly advise use safety gloves.

Do not overheat magnets

Do not overheat. NdFeB magnets are sensitive to heat. If you require operation above 80°C, ask us about special high-temperature series (H, SH, UH).

Machining danger

Dust created during machining of magnets is self-igniting. Avoid drilling into magnets without proper cooling and knowledge.

Pacemakers

Warning for patients: Powerful magnets disrupt medical devices. Keep minimum 30 cm distance or request help to work with the magnets.

Crushing force

Big blocks can crush fingers instantly. Under no circumstances place your hand between two attracting surfaces.

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

MP 40x20x5 / N38 - ring magnet

Detailed specification - MP 40x20x5 / N38 - ring magnet

Magnetic properties of material N38

Physical properties of sintered neodymium magnets Nd2Fe14B at 20°C

Engineering modeling of the magnet - data

Table 1: Static force (force vs gap) - interaction chart MP 40x20x5 / N38

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

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

Table 4: Steel thickness (saturation) - sheet metal selection MP 40x20x5 / N38

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

Table 9: Surface protection spec MP 40x20x5 / N38

Table 10: Electrical data (Flux) MP 40x20x5 / N38

Table 11: Submerged application MP 40x20x5 / N38

1. Wall mount (shear)

2. Efficiency vs thickness

3. Heat tolerance

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

Material specification

Ecology and recycling (GPSR)

Pulling force

Magnetic Induction

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HH 20x7.2 [M4] / N38 - through hole magnetic holder

MW 12x3 / N38 - cylindrical magnet

MW 12.5x2 / N38 - cylindrical magnet

Advantages and disadvantages of neodymium magnets.

Strengths

Limitations

Pull force analysis

Maximum lifting capacity of the magnet – what it depends on?

Determinants of lifting force in real conditions

Safety rules for work with NdFeB magnets

Powerful field

Protect data

Material brittleness

Choking Hazard

Keep away from electronics

Sensitization to coating

Do not overheat magnets

Machining danger

Pacemakers

Crushing force

Physical properties of sintered neodymium magnets Nd₂Fe₁₄B at 20°C

Table 1: Static force (force vs gap) - interaction chart
MP 40x20x5 / N38

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

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

Table 4: Steel thickness (saturation) - sheet metal selection
MP 40x20x5 / N38

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

Table 9: Surface protection spec
MP 40x20x5 / N38

Table 10: Electrical data (Flux)
MP 40x20x5 / N38

Table 11: Submerged application
MP 40x20x5 / N38