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MP 12x8/4x3 / 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 030395

GTIN/EAN: 5906301812326

5.00

Diameter

12 mm [±0,1 mm]

internal diameter Ø

8/4 mm [±0,1 mm]

Height

3 mm [±0,1 mm]

Weight

2.26 g

Magnetization Direction

↑ axial

Load capacity

2.21 kg / 21.72 N

Magnetic Induction

277.09 mT / 2771 Gs

Coating

[NiCuNi] Nickel

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1.427 ZŁ with VAT / pcs + price for transport

1.160 ZŁ net + 23% VAT / pcs

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Lifting power as well as structure of a neodymium magnet can be calculated with our force calculator.

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Physical properties - MP 12x8/4x3 / N38 - ring magnet

Specification / characteristics - MP 12x8/4x3 / N38 - ring magnet

properties

properties	values
Cat. no.	030395
GTIN/EAN	5906301812326
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	12 mm [±0,1 mm]
internal diameter Ø	8/4 mm [±0,1 mm]
Height	3 mm [±0,1 mm]
Weight	2.26 g
Magnetization Direction	↑ axial
Load capacity ~ ?	2.21 kg / 21.72 N
Magnetic Induction ~ ?	277.09 mT / 2771 Gs
Coating	[NiCuNi] Nickel
Manufacturing Tolerance	±0.1 mm

Magnetic properties of material N38

Specification / characteristics MP 12x8/4x3 / 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 - technical parameters

Presented values represent the direct effect of a engineering analysis. Results were calculated on algorithms for the class Nd₂Fe₁₄B. Real-world conditions may deviate from the simulation results. Treat these data as a preliminary roadmap for designers.

Table 1: Static force (pull vs gap) - characteristics
MP 12x8/4x3 / N38

Distance (mm)	Induction (Gauss) / mT	Pull Force (kg/lbs/g/N)	Risk Status
0 mm	2423 Gs 242.3 mT	2.21 kg / 4.87 lbs 2210.0 g / 21.7 N	strong
1 mm	2138 Gs 213.8 mT	1.72 kg / 3.79 lbs 1720.7 g / 16.9 N	safe
2 mm	1786 Gs 178.6 mT	1.20 kg / 2.65 lbs 1200.5 g / 11.8 N	safe
3 mm	1437 Gs 143.7 mT	0.78 kg / 1.71 lbs 777.8 g / 7.6 N	safe
5 mm	885 Gs 88.5 mT	0.29 kg / 0.65 lbs 294.7 g / 2.9 N	safe
10 mm	277 Gs 27.7 mT	0.03 kg / 0.06 lbs 28.9 g / 0.3 N	safe
15 mm	110 Gs 11.0 mT	0.00 kg / 0.01 lbs 4.6 g / 0.0 N	safe
20 mm	53 Gs 5.3 mT	0.00 kg / 0.00 lbs 1.1 g / 0.0 N	safe
30 mm	18 Gs 1.8 mT	0.00 kg / 0.00 lbs 0.1 g / 0.0 N	safe
50 mm	4 Gs 0.4 mT	0.00 kg / 0.00 lbs 0.0 g / 0.0 N	safe

Pulling power weakens drastically per each millimeter of spacing. Remember that every additional insulation layer (e.g., contamination, paint, rust) noticeably reduces the pull force. Magnets work strongest during direct contact; distance nullifies the power. Observe how quickly the pull force plummet, when the magnet does not touch directly to the steel surface. When designing the mounting, discard additional spacers.

Table 2: Slippage load (wall)
MP 12x8/4x3 / N38

Distance (mm)	Friction coefficient	Pull Force (kg/lbs/g/N)
0 mm	Stal (~0.2)	0.44 kg / 0.97 lbs 442.0 g / 4.3 N
1 mm	Stal (~0.2)	0.34 kg / 0.76 lbs 344.0 g / 3.4 N
2 mm	Stal (~0.2)	0.24 kg / 0.53 lbs 240.0 g / 2.4 N
3 mm	Stal (~0.2)	0.16 kg / 0.34 lbs 156.0 g / 1.5 N
5 mm	Stal (~0.2)	0.06 kg / 0.13 lbs 58.0 g / 0.6 N
10 mm	Stal (~0.2)	0.01 kg / 0.01 lbs 6.0 g / 0.1 N
15 mm	Stal (~0.2)	0.00 kg / 0.00 lbs 0.0 g / 0.0 N
20 mm	Stal (~0.2)	0.00 kg / 0.00 lbs 0.0 g / 0.0 N
30 mm	Stal (~0.2)	0.00 kg / 0.00 lbs 0.0 g / 0.0 N
50 mm	Stal (~0.2)	0.00 kg / 0.00 lbs 0.0 g / 0.0 N

This section shows the approximate holding capacity necessary to cause the sliding of the magnet downwards against a upright steel wall (assuming typical friction). The holding force is relative to the gap size between the magnet and the surface.

Table 3: Vertical assembly (sliding) - behavior on slippery surfaces
MP 12x8/4x3 / N38

Surface type	Friction coefficient / % Mocy	Max load (kg/lbs/g/N)
Raw steel	µ = 0.3 30% Nominalnej Siły	0.66 kg / 1.46 lbs 663.0 g / 6.5 N
Painted steel (standard)	µ = 0.2 20% Nominalnej Siły	0.44 kg / 0.97 lbs 442.0 g / 4.3 N
Oily/slippery steel	µ = 0.1 10% Nominalnej Siły	0.22 kg / 0.49 lbs 221.0 g / 2.2 N
Magnet with anti-slip rubber	µ = 0.5 50% Nominalnej Siły	1.11 kg / 2.44 lbs 1105.0 g / 10.8 N

When hanging a magnet on a vertical plane (e.g., a fridge), it will only hold only approx. 1/5 of its maximum pull force. Gravitational force and a weak degree of grip mean that holders slip faster than they pull off. Want to create a hanger? Remember that the sliding force is significantly lower than the perpendicular breakaway force. On a painted metal, the element will slide down under a noticeably lighter weight. Application of an anti-slip coating can effectively raise the stability.

Table 4: Material efficiency (substrate influence) - power losses
MP 12x8/4x3 / N38

Steel thickness (mm)	% power	Real pull force (kg/lbs/g/N)
0.5 mm	10%	0.22 kg / 0.49 lbs 221.0 g / 2.2 N
1 mm	25%	0.55 kg / 1.22 lbs 552.5 g / 5.4 N
2 mm	50%	1.11 kg / 2.44 lbs 1105.0 g / 10.8 N
3 mm	75%	1.66 kg / 3.65 lbs 1657.5 g / 16.3 N
5 mm	100%	2.21 kg / 4.87 lbs 2210.0 g / 21.7 N
10 mm	100%	2.21 kg / 4.87 lbs 2210.0 g / 21.7 N
11 mm	100%	2.21 kg / 4.87 lbs 2210.0 g / 21.7 N
12 mm	100%	2.21 kg / 4.87 lbs 2210.0 g / 21.7 N

A too thin steel cannot absorb the entire magnetic field, which squanders power of the holder. Should you install a neodymium to a weak sheet, the flux will pass right through and the attraction force will be weaker. To squeeze 100% of this magnet's power, you need a suitably thick backing of steel. The saturation phenomenon means that on sheet metal structures (e.g., car bodies), the magnet works worse. We suggest choosing the steel dimension from these parameters.

Table 5: Working in heat (stability) - power drop
MP 12x8/4x3 / N38

Ambient temp. (°C)	Power loss	Remaining pull (kg/lbs/g/N)	Status
20 °C	0.0%	2.21 kg / 4.87 lbs 2210.0 g / 21.7 N	OK
40 °C	-2.2%	2.16 kg / 4.77 lbs 2161.4 g / 21.2 N	OK
60 °C	-4.4%	2.11 kg / 4.66 lbs 2112.8 g / 20.7 N
80 °C	-6.6%	2.06 kg / 4.55 lbs 2064.1 g / 20.2 N
100 °C	-28.8%	1.57 kg / 3.47 lbs 1573.5 g / 15.4 N

Classic neodymiums change their properties parameters after exceeding the maximum temperature. Avoid high temperatures – heat can permanently damage this magnet. As the temperature rises, the magnet's power momentarily lowers. Refrain from using this product in hot environments higher than its safe range. Ignoring the limit will cause permanent loss of magnetic properties.

*Technical advisory: Thermal stability is determined by both grade, and the Permeance Coefficient Pc. Thin magnets (low permeance coefficient) are more susceptible to demagnetization sooner compared to rod magnets. The danger warning in the table indicates a risk of irreversible loss for this specific geometry.

Table 6: Magnet-Magnet interaction (repulsion) - field collision
MP 12x8/4x3 / N38

Gap (mm)	Attraction (kg/lbs) (N-S)	Shear Force (kg/lbs/g/N)	Repulsion (kg/lbs) (N-N)
0 mm	3.09 kg / 6.82 lbs 4 010 Gs	0.46 kg / 1.02 lbs 464 g / 4.6 N	N/A
1 mm	2.77 kg / 6.12 lbs 4 589 Gs	0.42 kg / 0.92 lbs 416 g / 4.1 N	2.50 kg / 5.50 lbs ~0 Gs
2 mm	2.41 kg / 5.31 lbs 4 276 Gs	0.36 kg / 0.80 lbs 361 g / 3.5 N	2.17 kg / 4.78 lbs ~0 Gs
3 mm	2.03 kg / 4.48 lbs 3 930 Gs	0.31 kg / 0.67 lbs 305 g / 3.0 N	1.83 kg / 4.04 lbs ~0 Gs
5 mm	1.36 kg / 3.00 lbs 3 216 Gs	0.20 kg / 0.45 lbs 204 g / 2.0 N	1.23 kg / 2.70 lbs ~0 Gs
10 mm	0.41 kg / 0.91 lbs 1 770 Gs	0.06 kg / 0.14 lbs 62 g / 0.6 N	0.37 kg / 0.82 lbs ~0 Gs
20 mm	0.04 kg / 0.09 lbs 554 Gs	0.01 kg / 0.01 lbs 6 g / 0.1 N	0.04 kg / 0.08 lbs ~0 Gs
50 mm	0.00 kg / 0.00 lbs 58 Gs	0.00 kg / 0.00 lbs 0 g / 0.0 N	0.00 kg / 0.00 lbs ~0 Gs
60 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
70 mm	0.00 kg / 0.00 lbs 23 Gs	0.00 kg / 0.00 lbs 0 g / 0.0 N	0.00 kg / 0.00 lbs ~0 Gs
80 mm	0.00 kg / 0.00 lbs 16 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 11 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 8 Gs	0.00 kg / 0.00 lbs 0 g / 0.0 N	0.00 kg / 0.00 lbs ~0 Gs

Two strong neodymiums interact from a wider radius than a magnet and steel combination. Such a system of two magnets creates a more powerful interaction and a further horizon of operation. Want to build a powerful holder? Apply two magnets instead of one magnet and a steel. Be careful that when attracting two neodymiums, the impact force is extreme. The repulsion force is slightly lower than the connection force, but still large.
*Flux density for N-N configuration drops to ~0 Gs at the geometric center of the gap (caused by magnetic field nullification).
Important: Calculations demonstrate friction force of a pair of identical magnets (friction coefficient ~0.15 for Ni-Ni layer).

Table 7: Hazards (implants) - warnings
MP 12x8/4x3 / N38

Object / Device	Limit (Gauss) / mT	Safe distance
Pacemaker	5 Gs (0.5 mT)	5.0 cm
Hearing aid	10 Gs (1.0 mT)	4.0 cm
Timepiece	20 Gs (2.0 mT)	3.0 cm
Mobile device	40 Gs (4.0 mT)	2.5 cm
Car key	50 Gs (5.0 mT)	2.5 cm
Payment card	400 Gs (40.0 mT)	1.0 cm
HDD hard drive	600 Gs (60.0 mT)	1.0 cm

Powerful magnet radiation is a large risk to electronic devices and medical implants. These neodymiums generate a field that destroys function of digital equipment. Remember: the invisible magnetic field acts through matter and glass. Exceptional care must be exercised by people with hearing aids and insulin pumps. The risk also applies to: automatic timepieces, car keys, membranes, and screens. Avoid contact with magnetic cards, hard drives, or precise measuring instruments.

Table 8: Collisions (cracking risk) - collision effects
MP 12x8/4x3 / N38

Start from (mm)	Speed (km/h)	Energy (J)
10 mm	31.79 km/h (8.83 m/s)	0.09 J
30 mm	54.63 km/h (15.17 m/s)	0.26 J
50 mm	70.52 km/h (19.59 m/s)	0.43 J
100 mm	99.73 km/h (27.70 m/s)	0.87 J

NdFeB products are very brittle – a collision with steel risks their cracking. Watch the impact speed – a magnet released freely becomes dangerous. Impact energy can trigger coating fragments or painful pinches to skin. Be sure to control the product during mounting so it doesn't hit with great force against the steel surface. A contact at a velocity of dozens of km/h ends with a crack of the neodymium. Use safety goggles when playing with powerful specimens.

Table 9: Surface protection spec
MP 12x8/4x3 / 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. The silver nickel coating also serves an aesthetic function but is not fully waterproof.

Table 10: Construction data (P_c)
MP 12x8/4x3 / N38

Parameter	Value	SI Unit / Description
Magnetic Flux	2 466 Mx	24.7 µWb
P_c Coefficient	0.32	Low (Flat)

Total magnetic flux passing through the pole surface. Key data when building generators and motors. The P_c coefficient determines the magnet's operating point.

Table 11: Underwater work (magnet fishing)
MP 12x8/4x3 / N38

Environment	Effective steel pull	Effect
Air (land)	2.21 kg	Standard
Water (riverbed)	2.53 kg (+0.32 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.

Contrary to myths, water does not block the magnetic field. Buoyancy helps in lifting finds.

1. Wall mount (shear)

*Warning: On a vertical surface, the magnet retains merely ~20% of its perpendicular strength.

2. Plate thickness effect

*Thin metal sheet (e.g. computer case) significantly reduces 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) = 0.32

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

Technical and environmental data

Chemical composition

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

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: 030395-2026

Measurement Calculator

Magnet pull force

Newtons (N)

Pounds (lbs)

Magnetic Induction

Tesla (T)

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The ring-shaped magnet MP 12x8/4x3 / N38 is created for mechanical fastening, where glue might fail or be insufficient. Thanks to the hole (often for a screw), this model enables quick installation to wood, wall, plastic, or metal. This product with a force of 2.21 kg works great as a door latch, speaker holder, or mounting element in devices.

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 too much pressure 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. Damage to the protective layer during assembly is the most common cause of rusting. This product is dedicated for indoor use. For outdoor applications, we recommend choosing rubberized holders or additional protection with varnish.

The inner hole diameter determines the maximum size of the mounting element. If the magnet does not have a chamfer (cone), we recommend using a screw with a flat or cylindrical head, or possibly using a washer. Aesthetic mounting requires selecting the appropriate head size.

This model is characterized by dimensions Ø12x3 mm and a weight of 2.26 g. The key parameter here is the holding force amounting to approximately 2.21 kg (force ~21.72 N). The product has a [NiCuNi] coating and is made of NdFeB material. Inner hole dimension: 8/4 mm.

These magnets are magnetized axially (through the thickness), which means one flat side is the N pole and the other is S. In the case of connecting two rings, make sure one is turned the right way. We do not offer paired sets with marked poles in this category, but they are easy to match manually.

Strengths and weaknesses of neodymium magnets.

Pros

In addition to their magnetic efficiency, neodymium magnets provide the following advantages:

They virtually do not lose strength, because even after ten years the performance loss is only ~1% (based on calculations),
Magnets perfectly protect themselves against loss of magnetization caused by ambient magnetic noise,
The use of an aesthetic finish of noble metals (nickel, gold, silver) causes the element to be more visually attractive,
Neodymium magnets deliver maximum magnetic induction on a contact point, which increases force concentration,
Made from properly selected components, these magnets show impressive resistance to high heat, enabling them to function (depending on their shape) at temperatures up to 230°C and above...
Thanks to flexibility in shaping and the ability to adapt to unusual requirements,
Wide application in advanced technology sectors – they find application in mass storage devices, electric motors, advanced medical instruments, and technologically advanced constructions.
Relatively small size with high pulling force – neodymium magnets offer strong magnetic field in small dimensions, which makes them useful in compact constructions

Weaknesses

Cons of neodymium magnets and proposals for their use:

They are prone to damage upon heavy impacts. To avoid cracks, it is worth securing magnets using a steel holder. Such protection not only shields the magnet but also improves its resistance to damage
When exposed to high temperature, neodymium magnets suffer a drop in power. Often, when the temperature exceeds 80°C, their power decreases (depending on the size and shape of the magnet). For those who need magnets for extreme conditions, we offer [AH] versions withstanding up to 230°C
They rust in a humid environment - during use outdoors we suggest using waterproof magnets e.g. in rubber, plastic
We suggest casing - magnetic mount, due to difficulties in creating nuts inside the magnet and complex forms.
Health risk related to microscopic parts of magnets can be dangerous, in case of ingestion, which gains importance in the aspect of protecting the youngest. It is also worth noting that small elements of these products are able to complicate diagnosis medical after entering the body.
Due to neodymium price, their price exceeds standard values,

Pull force analysis

Maximum lifting capacity of the magnet – what contributes to it?

Information about lifting capacity was determined for optimal configuration, taking into account:

on a plate made of structural steel, optimally conducting the magnetic field
possessing a thickness of minimum 10 mm to ensure full flux closure
with a plane perfectly flat
under conditions of no distance (metal-to-metal)
during detachment in a direction perpendicular to the plane
in stable room temperature

Lifting capacity in practice – influencing factors

Effective lifting capacity is influenced by working environment parameters, mainly (from most important):

Distance (betwixt the magnet and the metal), since even a tiny clearance (e.g. 0.5 mm) leads to a drastic drop in force by up to 50% (this also applies to varnish, corrosion or debris).
Force direction – declared lifting capacity refers to detachment vertically. When slipping, the magnet holds much less (typically approx. 20-30% of nominal force).
Plate thickness – insufficiently thick steel causes magnetic saturation, causing part of the power to be lost into the air.
Steel grade – ideal substrate is high-permeability steel. Cast iron may have worse magnetic properties.
Surface finish – full contact is obtained only on smooth steel. Any scratches and bumps reduce the real contact area, weakening the magnet.
Thermal conditions – neodymium magnets have a negative temperature coefficient. At higher temperatures they are weaker, and in frost they can be stronger (up to a certain limit).

Lifting capacity testing was performed on plates with a smooth surface of optimal thickness, under perpendicular forces, in contrast under parallel forces the load capacity is reduced by as much as 75%. In addition, even a small distance between the magnet’s surface and the plate decreases the holding force.

Warnings

Material brittleness

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

Fire risk

Mechanical processing of NdFeB material poses a fire hazard. Neodymium dust oxidizes rapidly with oxygen and is hard to extinguish.

Immense force

Exercise caution. Neodymium magnets act from a distance and connect with huge force, often faster than you can move away.

Keep away from children

NdFeB magnets are not intended for children. Swallowing multiple magnets can lead to them pinching intestinal walls, which poses a direct threat to life and necessitates immediate surgery.

Life threat

For implant holders: Powerful magnets disrupt electronics. Maintain minimum 30 cm distance or request help to handle the magnets.

Hand protection

Risk of injury: The attraction force is so great that it can cause blood blisters, crushing, and even bone fractures. Use thick gloves.

Magnetic interference

A powerful magnetic field negatively affects the operation of compasses in smartphones and navigation systems. Do not bring magnets close to a smartphone to avoid breaking the sensors.

Data carriers

Intense magnetic fields can erase data on credit cards, hard drives, and storage devices. Keep a distance of min. 10 cm.

Nickel allergy

Certain individuals have a sensitization to nickel, which is the typical protective layer for NdFeB magnets. Frequent touching can result in dermatitis. We strongly advise wear safety gloves.

Permanent damage

Do not overheat. Neodymium magnets are sensitive to temperature. If you need resistance above 80°C, look for special high-temperature series (H, SH, UH).

Danger! Details about hazards in the article: Magnet Safety Guide.

MP 12x8/4x3 / N38 - ring magnet

Physical properties - MP 12x8/4x3 / N38 - ring magnet

Magnetic properties of material N38

Physical properties of sintered neodymium magnets Nd2Fe14B at 20°C

Engineering modeling of the magnet - technical parameters

Table 1: Static force (pull vs gap) - characteristics MP 12x8/4x3 / N38

Table 2: Slippage load (wall) MP 12x8/4x3 / N38

Table 3: Vertical assembly (sliding) - behavior on slippery surfaces MP 12x8/4x3 / N38

Table 4: Material efficiency (substrate influence) - power losses MP 12x8/4x3 / N38

Table 5: Working in heat (stability) - power drop MP 12x8/4x3 / N38

Table 6: Magnet-Magnet interaction (repulsion) - field collision MP 12x8/4x3 / N38

Table 7: Hazards (implants) - warnings MP 12x8/4x3 / N38

Table 8: Collisions (cracking risk) - collision effects MP 12x8/4x3 / N38

Table 9: Surface protection spec MP 12x8/4x3 / N38

Table 10: Construction data (Pc) MP 12x8/4x3 / N38

Table 11: Underwater work (magnet fishing) MP 12x8/4x3 / N38

1. Wall mount (shear)

2. Plate thickness effect

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 and weaknesses of neodymium magnets.

Pros

Weaknesses

Pull force analysis

Maximum lifting capacity of the magnet – what contributes to it?

Lifting capacity in practice – influencing factors

Warnings

Material brittleness

Fire risk

Immense force

Keep away from children

Life threat

Hand protection

Magnetic interference

Data carriers

Nickel allergy

Permanent damage

Physical properties of sintered neodymium magnets Nd₂Fe₁₄B at 20°C

Table 1: Static force (pull vs gap) - characteristics
MP 12x8/4x3 / N38

Table 2: Slippage load (wall)
MP 12x8/4x3 / N38

Table 3: Vertical assembly (sliding) - behavior on slippery surfaces
MP 12x8/4x3 / N38

Table 4: Material efficiency (substrate influence) - power losses
MP 12x8/4x3 / N38

Table 5: Working in heat (stability) - power drop
MP 12x8/4x3 / N38

Table 6: Magnet-Magnet interaction (repulsion) - field collision
MP 12x8/4x3 / N38

Table 7: Hazards (implants) - warnings
MP 12x8/4x3 / N38

Table 8: Collisions (cracking risk) - collision effects
MP 12x8/4x3 / N38

Table 9: Surface protection spec
MP 12x8/4x3 / N38

Table 10: Construction data (P_c)
MP 12x8/4x3 / N38

Table 11: Underwater work (magnet fishing)
MP 12x8/4x3 / N38