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MP 20x8/4x5 / 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 030333

GTIN/EAN: 5906301812272

5.00

Diameter

20 mm [±0,1 mm]

internal diameter Ø

8/4 mm [±0,1 mm]

Height

5 mm [±0,1 mm]

Weight

11.31 g

Magnetization Direction

↑ axial

Load capacity

6.65 kg / 65.21 N

Magnetic Induction

277.16 mT / 2772 Gs

Coating

[NiCuNi] Nickel

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7.75 ZŁ with VAT / pcs + price for transport

6.30 ZŁ net + 23% VAT / pcs

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Product card - MP 20x8/4x5 / N38 - ring magnet

Specification / characteristics - MP 20x8/4x5 / N38 - ring magnet

properties

properties	values
Cat. no.	030333
GTIN/EAN	5906301812272
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	20 mm [±0,1 mm]
internal diameter Ø	8/4 mm [±0,1 mm]
Height	5 mm [±0,1 mm]
Weight	11.31 g
Magnetization Direction	↑ axial
Load capacity ~ ?	6.65 kg / 65.21 N
Magnetic Induction ~ ?	277.16 mT / 2772 Gs
Coating	[NiCuNi] Nickel
Manufacturing Tolerance	±0.1 mm

Magnetic properties of material N38

Specification / characteristics MP 20x8/4x5 / 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 modeling of the assembly - report

The following values constitute the outcome of a engineering simulation. Results rely on algorithms for the material Nd₂Fe₁₄B. Real-world performance may deviate from the simulation results. Use these calculations as a preliminary roadmap when designing systems.

Table 1: Static force (force vs gap) - characteristics
MP 20x8/4x5 / N38

Distance (mm)	Induction (Gauss) / mT	Pull Force (kg/lbs/g/N)	Risk Status
0 mm	2424 Gs 242.4 mT	6.65 kg / 14.66 LBS 6650.0 g / 65.2 N	medium risk
1 mm	2265 Gs 226.5 mT	5.81 kg / 12.80 LBS 5807.9 g / 57.0 N	medium risk
2 mm	2070 Gs 207.0 mT	4.85 kg / 10.69 LBS 4851.0 g / 47.6 N	medium risk
3 mm	1858 Gs 185.8 mT	3.91 kg / 8.61 LBS 3906.5 g / 38.3 N	medium risk
5 mm	1437 Gs 143.7 mT	2.34 kg / 5.16 LBS 2338.7 g / 22.9 N	medium risk
10 mm	691 Gs 69.1 mT	0.54 kg / 1.19 LBS 540.5 g / 5.3 N	weak grip
15 mm	343 Gs 34.3 mT	0.13 kg / 0.29 LBS 133.3 g / 1.3 N	weak grip
20 mm	186 Gs 18.6 mT	0.04 kg / 0.09 LBS 39.3 g / 0.4 N	weak grip
30 mm	70 Gs 7.0 mT	0.01 kg / 0.01 LBS 5.5 g / 0.1 N	weak grip
50 mm	18 Gs 1.8 mT	0.00 kg / 0.00 LBS 0.4 g / 0.0 N	weak grip

Pulling power weakens significantly with every subsequent millimeter of spacing. Remember that even the smallest gap (e.g., dirt, varnish, veneer) significantly diminishes the holding power. Magnets hold strongest at the point of direct contact; distance nullifies the force. Notice how flashily the parameters plummet, when the magnet does not touch tightly to the steel surface. When planning the arrangement, eliminate redundant distances.

Table 2: Sliding capacity (wall)
MP 20x8/4x5 / N38

Distance (mm)	Friction coefficient	Pull Force (kg/lbs/g/N)
0 mm	Stal (~0.2)	1.33 kg / 2.93 LBS 1330.0 g / 13.0 N
1 mm	Stal (~0.2)	1.16 kg / 2.56 LBS 1162.0 g / 11.4 N
2 mm	Stal (~0.2)	0.97 kg / 2.14 LBS 970.0 g / 9.5 N
3 mm	Stal (~0.2)	0.78 kg / 1.72 LBS 782.0 g / 7.7 N
5 mm	Stal (~0.2)	0.47 kg / 1.03 LBS 468.0 g / 4.6 N
10 mm	Stal (~0.2)	0.11 kg / 0.24 LBS 108.0 g / 1.1 N
15 mm	Stal (~0.2)	0.03 kg / 0.06 LBS 26.0 g / 0.3 N
20 mm	Stal (~0.2)	0.01 kg / 0.02 LBS 8.0 g / 0.1 N
30 mm	Stal (~0.2)	0.00 kg / 0.00 LBS 2.0 g / 0.0 N
50 mm	Stal (~0.2)	0.00 kg / 0.00 LBS 0.0 g / 0.0 N

The following data presents the estimated force sufficient to start the sliding of the magnet down against a upright steel wall (considering standard friction coefficient). This parameter is a function of the air gap between the magnet and the metal.

Table 3: Wall mounting (shearing) - behavior on slippery surfaces
MP 20x8/4x5 / N38

Surface type	Friction coefficient / % Mocy	Max load (kg/lbs/g/N)
Raw steel	µ = 0.3 30% Nominalnej Siły	2.00 kg / 4.40 LBS 1995.0 g / 19.6 N
Painted steel (standard)	µ = 0.2 20% Nominalnej Siły	1.33 kg / 2.93 LBS 1330.0 g / 13.0 N
Oily/slippery steel	µ = 0.1 10% Nominalnej Siły	0.67 kg / 1.47 LBS 665.0 g / 6.5 N
Magnet with anti-slip rubber	µ = 0.5 50% Nominalnej Siły	3.33 kg / 7.33 LBS 3325.0 g / 32.6 N

When placing a element on a upright surface (e.g., a car body), it will maintain just about 1/5 of its nominal power. Gravitational force as well as a weak degree of grip influence the fact that products slide down easier than they pull off. Designing a hanger? Note that the shear force is noticeably lower than the perpendicular breakaway force. On a slippery surface, the magnet will slide down under a much lighter weight. Utilizing a rubberized layer can significantly increase the grip.

Table 4: Steel thickness (substrate influence) - sheet metal selection
MP 20x8/4x5 / N38

Steel thickness (mm)	% power	Real pull force (kg/lbs/g/N)
0.5 mm	10%	0.67 kg / 1.47 LBS 665.0 g / 6.5 N
1 mm	25%	1.66 kg / 3.67 LBS 1662.5 g / 16.3 N
2 mm	50%	3.33 kg / 7.33 LBS 3325.0 g / 32.6 N
3 mm	75%	4.99 kg / 11.00 LBS 4987.5 g / 48.9 N
5 mm	100%	6.65 kg / 14.66 LBS 6650.0 g / 65.2 N
10 mm	100%	6.65 kg / 14.66 LBS 6650.0 g / 65.2 N
11 mm	100%	6.65 kg / 14.66 LBS 6650.0 g / 65.2 N
12 mm	100%	6.65 kg / 14.66 LBS 6650.0 g / 65.2 N

A thin sheet cannot conduct the full magnetic flux, which wastes potential of the holder. Should you install a neodymium to a thin surface, the magnetism will penetrate right through and the attraction force will be weaker. To achieve the maximum of this magnet's power, you require a sufficiently solid backing of steel. The saturation phenomenon means that on sheet metal structures (e.g., car bodies), the product shows lower pull force. We advise picking the steel dimension based on the following data.

Table 5: Thermal stability (material behavior) - resistance threshold
MP 20x8/4x5 / N38

Ambient temp. (°C)	Power loss	Remaining pull (kg/lbs/g/N)	Status
20 °C	0.0%	6.65 kg / 14.66 LBS 6650.0 g / 65.2 N	OK
40 °C	-2.2%	6.50 kg / 14.34 LBS 6503.7 g / 63.8 N	OK
60 °C	-4.4%	6.36 kg / 14.02 LBS 6357.4 g / 62.4 N
80 °C	-6.6%	6.21 kg / 13.69 LBS 6211.1 g / 60.9 N
100 °C	-28.8%	4.73 kg / 10.44 LBS 4734.8 g / 46.4 N

Ordinary NdFeB products irreversibly lose strength after exceeding the maximum temperature. Avoid high temperatures – excessive heat can irreversibly damage this product. With increasing heat, the magnet's power momentarily decreases. Avoid using this magnet close to ovens exceeding its operating temperature limit. Ignoring the limit will cause permanent loss of magnetic properties.

*Important note: Thermal stability is determined by both grade, but also on the magnet's shape. Low-profile magnets (low permeance coefficient) may lose charge permanently at lower temperatures compared to rod magnets. Red status in the table points to a risk of irreversible loss for this particular item.

Table 6: Magnet-Magnet interaction (repulsion) - field range
MP 20x8/4x5 / N38

Gap (mm)	Attraction (kg/lbs) (N-S)	Lateral Force (kg/lbs/g/N)	Repulsion (kg/lbs) (N-N)
0 mm	9.28 kg / 20.47 LBS 4 012 Gs	1.39 kg / 3.07 LBS 1393 g / 13.7 N	N/A
1 mm	8.73 kg / 19.25 LBS 4 701 Gs	1.31 kg / 2.89 LBS 1310 g / 12.8 N	7.86 kg / 17.33 LBS ~0 Gs
2 mm	8.11 kg / 17.88 LBS 4 530 Gs	1.22 kg / 2.68 LBS 1216 g / 11.9 N	7.30 kg / 16.09 LBS ~0 Gs
3 mm	7.45 kg / 16.42 LBS 4 342 Gs	1.12 kg / 2.46 LBS 1117 g / 11.0 N	6.70 kg / 14.78 LBS ~0 Gs
5 mm	6.10 kg / 13.45 LBS 3 930 Gs	0.92 kg / 2.02 LBS 915 g / 9.0 N	5.49 kg / 12.11 LBS ~0 Gs
10 mm	3.27 kg / 7.20 LBS 2 875 Gs	0.49 kg / 1.08 LBS 490 g / 4.8 N	2.94 kg / 6.48 LBS ~0 Gs
20 mm	0.75 kg / 1.66 LBS 1 382 Gs	0.11 kg / 0.25 LBS 113 g / 1.1 N	0.68 kg / 1.50 LBS ~0 Gs
50 mm	0.02 kg / 0.04 LBS 220 Gs	0.00 kg / 0.01 LBS 3 g / 0.0 N	0.02 kg / 0.04 LBS ~0 Gs
60 mm	0.01 kg / 0.02 LBS 139 Gs	0.00 kg / 0.00 LBS 1 g / 0.0 N	0.00 kg / 0.00 LBS ~0 Gs
70 mm	0.00 kg / 0.01 LBS 93 Gs	0.00 kg / 0.00 LBS 1 g / 0.0 N	0.00 kg / 0.00 LBS ~0 Gs
80 mm	0.00 kg / 0.00 LBS 65 Gs	0.00 kg / 0.00 LBS 0 g / 0.0 N	0.00 kg / 0.00 LBS ~0 Gs
90 mm	0.00 kg / 0.00 LBS 47 Gs	0.00 kg / 0.00 LBS 0 g / 0.0 N	0.00 kg / 0.00 LBS ~0 Gs
100 mm	0.00 kg / 0.00 LBS 35 Gs	0.00 kg / 0.00 LBS 0 g / 0.0 N	0.00 kg / 0.00 LBS ~0 Gs

Two magnetic products attract each other from a significantly greater distance than a magnet and sheet setup. Such a system of magnet-to-magnet generates a stronger field and a further horizon of action. Planning to create 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 extreme. The levitation is marginally weaker than the attraction, but still significant.
*The magnetic induction in repulsion mode drops to ~0 Gs at the geometric center of the gap (resulting from vector opposition).
* Calculations show sliding force of dual same neodymium magnets (friction coefficient ~0.15 for Ni-Ni layer).

Table 7: Hazards (implants) - warnings
MP 20x8/4x5 / N38

Object / Device	Limit (Gauss) / mT	Safe distance
Pacemaker	5 Gs (0.5 mT)	8.0 cm
Hearing aid	10 Gs (1.0 mT)	6.5 cm
Timepiece	20 Gs (2.0 mT)	5.0 cm
Mobile device	40 Gs (4.0 mT)	4.0 cm
Remote	50 Gs (5.0 mT)	3.5 cm
Payment card	400 Gs (40.0 mT)	1.5 cm
HDD hard drive	600 Gs (60.0 mT)	1.5 cm

A strong magnetic field is a large risk to IT equipment as well as pacemakers. These magnets generate a flux that destroys function of digital equipment. Remember: the invisible magnetic field passes through tissues and housings. Special caution must be taken by people with hearing aids and drug dispensers. The risk also applies to: automatic timepieces, car keys, speakers, and displays. Do not place the magnet near cards, HDD media, or precise measuring instruments.

Table 8: Dynamics (cracking risk) - collision effects
MP 20x8/4x5 / N38

Start from (mm)	Speed (km/h)	Energy (J)
10 mm	25.67 km/h (7.13 m/s)	0.29 J
30 mm	42.38 km/h (11.77 m/s)	0.78 J
50 mm	54.68 km/h (15.19 m/s)	1.30 J
100 mm	77.33 km/h (21.48 m/s)	2.61 J

Magnetic elements are prone to chipping – a collision with steel can result in shattering. Control the attraction moment – a magnet released freely turns into a projectile. Kinetic force can trigger coating fragments or dangerous crushing to fingers. Be sure to control the product during bringing near metal so it doesn't slam with momentum against the steel surface. A collision at high speed ends with a crack of the neodymium. Wear eye protection when handling with large magnets.

Table 9: Corrosion resistance
MP 20x8/4x5 / 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)

For outdoor applications, an epoxy coating is required; standard nickel is intended for indoor use. Improper coating selection is the most common cause of magnet failure over time.

Table 10: Electrical data (P_c)
MP 20x8/4x5 / N38

Parameter	Value	SI Unit / Description
Magnetic Flux	7 218 Mx	72.2 µWb
P_c Coefficient	0.31	Low (Flat)

Total magnetic flux emitted by the pole surface. Essential parameter for generator designers and motors. P_c value defines the magnet's operating point.

Table 11: Submerged application
MP 20x8/4x5 / N38

Environment	Effective steel pull	Effect
Air (land)	6.65 kg	Standard
Water (riverbed)	7.61 kg (+0.96 kg buoyancy gain)	+14.5%

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

In water, the magnet feels stronger thanks to Archimedes' principle. Buoyancy helps in lifting finds.

1. Sliding resistance

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

2. Efficiency vs thickness

*Thin metal sheet (e.g. 0.5mm PC case) severely reduces the holding force.

3. Power loss vs temp

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

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

chart generated for the permeance coefficient P_c (Permeance Coefficient) = 0.31

The chart above illustrates the magnetic characteristics of the material within the second quadrant of the hysteresis loop. The solid red line represents the demagnetization curve (material potential), while the dashed blue line is the load line based on the magnet's geometry. The P_c (Permeance Coefficient), also known as the load line slope, is a dimensionless value that describes the relationship between the magnet's shape and its magnetic stability. The intersection of these two lines (the black dot) is the operating point — it determines the actual magnetic flux density generated by the magnet in this specific configuration. A higher P_c value means the magnet is more 'slender' (tall relative to its area), resulting in a higher operating point and better resistance to irreversible demagnetization caused by external fields or temperature. A value of 0.42 is relatively low (typical for flat magnets), meaning the operating point is closer to the 'knee' of the curve — caution is advised when operating at temperatures near the maximum limit to avoid strength loss.

Technical specification and ecology

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%

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: 030333-2026

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It is ideally suited for places where solid attachment of the magnet to the substrate is required without the risk of detachment. 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 20x8/4x5 / 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. 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 does not ensure full waterproofing. Damage to the protective layer during assembly is the most common cause of rusting. 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 8/4 mm fits this model. For magnets with a straight hole, a conical head can act like a wedge and burst the magnet. Always check that the screw head is not larger than the outer diameter of the magnet (20 mm), so it doesn't protrude beyond the outline.

The presented product is a ring magnet with dimensions Ø20 mm (outer diameter) and height 5 mm. The pulling force of this model is an impressive 6.65 kg, which translates to 65.21 N in newtons. The mounting hole diameter is precisely 8/4 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). We do not offer paired sets with marked poles in this category, but they are easy to match manually.

Strengths as well as weaknesses of rare earth magnets.

Advantages

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

They retain attractive force for nearly ten years – the loss is just ~1% (based on simulations),
They do not lose their magnetic properties even under external field action,
A magnet with a shiny gold surface is more attractive,
Magnets possess maximum magnetic induction on the working surface,
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...
Possibility of individual forming and adjusting to complex conditions,
Versatile presence in high-tech industry – they find application in magnetic memories, brushless drives, medical equipment, also other advanced devices.
Relatively small size with high pulling force – neodymium magnets offer impressive pulling force in tiny dimensions, which allows their use in compact constructions

Limitations

Disadvantages of neodymium magnets:

Susceptibility to cracking is one of their disadvantages. Upon intense impact they can break. We advise keeping them in a strong case, which not only protects them against impacts but also raises their durability
Neodymium magnets lose their strength under the influence of heating. As soon as 80°C is exceeded, many of them start losing their force. Therefore, we recommend our special magnets marked [AH], which maintain durability even at temperatures up to 230°C
When exposed to humidity, magnets start to rust. For applications outside, it is recommended to use protective magnets, such as magnets in rubber or plastics, which secure oxidation and corrosion.
Due to limitations in realizing threads and complicated shapes in magnets, we recommend using cover - magnetic mount.
Possible danger resulting from small fragments of magnets are risky, when accidentally swallowed, which is particularly important in the context of child safety. It is also worth noting that tiny parts of these products can be problematic in diagnostics medical after entering the body.
With mass production the cost of neodymium magnets is a challenge,

Holding force characteristics

Best holding force of the magnet in ideal parameters – what contributes to it?

Information about lifting capacity was defined for ideal contact conditions, taking into account:

on a plate made of mild steel, effectively closing the magnetic field
whose transverse dimension is min. 10 mm
characterized by lack of roughness
with direct contact (without paint)
under vertical force vector (90-degree angle)
at ambient temperature room level

Determinants of lifting force in real conditions

It is worth knowing that the magnet holding will differ subject to the following factors, in order of importance:

Distance – existence of foreign body (rust, dirt, gap) interrupts the magnetic circuit, which lowers power rapidly (even by 50% at 0.5 mm).
Pull-off angle – remember that the magnet holds strongest perpendicularly. Under sliding down, the holding force drops significantly, often to levels of 20-30% of the maximum value.
Wall thickness – thin material does not allow full use of the magnet. Magnetic flux passes through the material instead of generating force.
Material type – ideal substrate is high-permeability steel. Cast iron may attract less.
Surface condition – smooth surfaces ensure maximum contact, which increases field saturation. Rough surfaces weaken the grip.
Thermal conditions – NdFeB sinters have a sensitivity to temperature. When it is hot they are weaker, and at low temperatures they can be stronger (up to a certain limit).

Holding force was tested on a smooth steel plate of 20 mm thickness, when the force acted perpendicularly, whereas under shearing force the holding force is lower. In addition, even a slight gap between the magnet and the plate decreases the holding force.

Safe handling of neodymium magnets

Magnets are brittle

Beware of splinters. Magnets can fracture upon violent connection, launching sharp fragments into the air. Wear goggles.

Compass and GPS

Be aware: neodymium magnets produce a field that confuses precision electronics. Maintain a separation from your mobile, tablet, and GPS.

Safe operation

Before use, read the rules. Sudden snapping can break the magnet or hurt your hand. Be predictive.

Bodily injuries

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

Threat to electronics

Avoid bringing magnets close to a wallet, laptop, or TV. The magnetism can permanently damage these devices and wipe information from cards.

Mechanical processing

Drilling and cutting of NdFeB material poses a fire hazard. Neodymium dust oxidizes rapidly with oxygen and is difficult to extinguish.

Demagnetization risk

Regular neodymium magnets (N-type) undergo demagnetization when the temperature exceeds 80°C. This process is irreversible.

Medical implants

For implant holders: Strong magnetic fields disrupt electronics. Keep minimum 30 cm distance or request help to handle the magnets.

Danger to the youngest

Product intended for adults. Tiny parts can be swallowed, causing intestinal necrosis. Keep out of reach of kids and pets.

Allergic reactions

A percentage of the population have a hypersensitivity to nickel, which is the typical protective layer for NdFeB magnets. Prolonged contact may cause a rash. We suggest use safety gloves.

Security! Learn more about risks in the article: Safety of working with magnets.

MP 20x8/4x5 / N38 - ring magnet

Product card - MP 20x8/4x5 / N38 - ring magnet

Magnetic properties of material N38

Physical properties of sintered neodymium magnets Nd2Fe14B at 20°C

Physical modeling of the assembly - report

Table 1: Static force (force vs gap) - characteristics MP 20x8/4x5 / N38

Table 2: Sliding capacity (wall) MP 20x8/4x5 / N38

Table 3: Wall mounting (shearing) - behavior on slippery surfaces MP 20x8/4x5 / N38

Table 4: Steel thickness (substrate influence) - sheet metal selection MP 20x8/4x5 / N38

Table 5: Thermal stability (material behavior) - resistance threshold MP 20x8/4x5 / N38

Table 6: Magnet-Magnet interaction (repulsion) - field range MP 20x8/4x5 / N38

Table 7: Hazards (implants) - warnings MP 20x8/4x5 / N38

Table 8: Dynamics (cracking risk) - collision effects MP 20x8/4x5 / N38

Table 9: Corrosion resistance MP 20x8/4x5 / N38

Table 10: Electrical data (Pc) MP 20x8/4x5 / N38

Table 11: Submerged application MP 20x8/4x5 / N38

1. Sliding resistance

2. Efficiency vs thickness

3. Power loss vs temp

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

Chemical composition

Ecology and recycling (GPSR)

Magnet pull force

Magnetic Induction

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Strengths as well as weaknesses of rare earth magnets.

Advantages

Limitations

Holding force characteristics

Best holding force of the magnet in ideal parameters – what contributes to it?

Determinants of lifting force in real conditions

Safe handling of neodymium magnets

Magnets are brittle

Compass and GPS

Safe operation

Bodily injuries

Threat to electronics

Mechanical processing

Demagnetization risk

Medical implants

Danger to the youngest

Allergic reactions

Physical properties of sintered neodymium magnets Nd₂Fe₁₄B at 20°C

Table 1: Static force (force vs gap) - characteristics
MP 20x8/4x5 / N38

Table 2: Sliding capacity (wall)
MP 20x8/4x5 / N38

Table 3: Wall mounting (shearing) - behavior on slippery surfaces
MP 20x8/4x5 / N38

Table 4: Steel thickness (substrate influence) - sheet metal selection
MP 20x8/4x5 / N38

Table 5: Thermal stability (material behavior) - resistance threshold
MP 20x8/4x5 / N38

Table 6: Magnet-Magnet interaction (repulsion) - field range
MP 20x8/4x5 / N38

Table 7: Hazards (implants) - warnings
MP 20x8/4x5 / N38

Table 8: Dynamics (cracking risk) - collision effects
MP 20x8/4x5 / N38

Table 9: Corrosion resistance
MP 20x8/4x5 / N38

Table 10: Electrical data (P_c)
MP 20x8/4x5 / N38

Table 11: Submerged application
MP 20x8/4x5 / N38