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MP 15x7/3.5x5 / N38 - ring magnet

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

ring magnet

Catalog no 030390

GTIN/EAN: 5906301812302

5.00

Load capacity 5.09 kg / 49.95 N Magnetic Induction 343.70 mT / 3437 Gs

Diameter: 15 mm [±0,1 mm]
internal diameter Ø: 7/3.5 mm [±0,1 mm]
Height: 5 mm [±0,1 mm]
Weight: 6.27 g
Magnetization Direction: ↑ axial
Coating: [NiCuNi] Nickel

see technical data »

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3.44 zł with VAT (23% VAT) / pcs

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Frequently asked questions

What is the hole in a ring magnet for?

For mounting on a screw or a shaft. The bore may be cylindrical or countersunk for a screw head. The hole removes magnet volume, so a ring holds less than a disc of the same outside diameter.

What is the polarisation?

Axial as standard — poles on the flat faces of the ring. Diametrical polarisation is made to order.

What sizes are available?

Outside diameter from 5 to 62 mm from stock. To order up to 200 mm outside diameter, 180 mm bore and 40 mm height, with a lead time of 25–35 days.

Guides from the knowledge base

Engineering report for this magnet

Full PDF analysis: pull and shear force, effect of distance, temperature and plate thickness, safety distances and the demagnetization curve.

PDF report Calculator

Want to talk magnets?

Call us now +48 888 99 98 98 alternatively let us know using contact form the contact section.
Specifications and structure of a neodymium magnet can be estimated using our power calculator.

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Technical details - MP 15x7/3.5x5 / N38 - ring magnet

Specification / characteristics - MP 15x7/3.5x5 / N38 - ring magnet

properties

properties	values
Cat. no.	030390
GTIN/EAN	5906301812302
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	15 mm [±0,1 mm]
internal diameter Ø	7/3.5 mm [±0,1 mm]
Height	5 mm [±0,1 mm]
Weight	6.27 g
Magnetization Direction	↑ axial
Load capacity ~ ?	5.09 kg / 49.95 N
Magnetic Induction ~ ?	343.70 mT / 3437 Gs
Coating	[NiCuNi] Nickel
Manufacturing Tolerance	±0.1 mm

Magnetic properties of material N38

Specification / characteristics MP 15x7/3.5x5 / 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	310	°C
Curie Temperature TF	590	°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 simulation of the magnet - data

Presented values are the outcome of a physical calculation. Results rely on models for the class Nd₂Fe₁₄B. Real-world conditions might slightly differ from theoretical values. Use these data as a supplementary guide for designers.

Table 1: Static pull force (force vs distance) - power drop
MP 15x7/3.5x5 / N38

Distance (mm)	Induction (Gauss) / mT	Pull Force (kg/lbs/g/N)	Risk Status
0 mm	3054 Gs 305.4 mT	5.09 kg / 11.22 pounds 5090.0 g / 49.9 N	strong
1 mm	2736 Gs 273.6 mT	4.09 kg / 9.01 pounds 4085.7 g / 40.1 N	strong
2 mm	2372 Gs 237.2 mT	3.07 kg / 6.77 pounds 3069.9 g / 30.1 N	strong
3 mm	2007 Gs 200.7 mT	2.20 kg / 4.84 pounds 2197.4 g / 21.6 N	strong
5 mm	1377 Gs 137.7 mT	1.03 kg / 2.28 pounds 1034.5 g / 10.1 N	weak grip
10 mm	526 Gs 52.6 mT	0.15 kg / 0.33 pounds 151.3 g / 1.5 N	weak grip
15 mm	232 Gs 23.2 mT	0.03 kg / 0.06 pounds 29.3 g / 0.3 N	weak grip
20 mm	118 Gs 11.8 mT	0.01 kg / 0.02 pounds 7.6 g / 0.1 N	weak grip
30 mm	42 Gs 4.2 mT	0.00 kg / 0.00 pounds 0.9 g / 0.0 N	weak grip
50 mm	10 Gs 1.0 mT	0.00 kg / 0.00 pounds 0.1 g / 0.0 N	weak grip

Magnetic force weakens significantly with every mm of gap. Remember that even a very thin break (e.g., dirt, varnish, dust) noticeably weakens the grip. Magnets work strongest during direct contact; distance kills the power. Analyze how flashily the pull force plummet, when the magnet does not touch flatly to the metal substrate. When planning the mounting, discard unnecessary gaps.

Table 2: Slippage hold (wall)
MP 15x7/3.5x5 / N38

Distance (mm)	Friction coefficient	Pull Force (kg/lbs/g/N)
0 mm	Stal (~0.2)	1.02 kg / 2.24 pounds 1018.0 g / 10.0 N
1 mm	Stal (~0.2)	0.82 kg / 1.80 pounds 818.0 g / 8.0 N
2 mm	Stal (~0.2)	0.61 kg / 1.35 pounds 614.0 g / 6.0 N
3 mm	Stal (~0.2)	0.44 kg / 0.97 pounds 440.0 g / 4.3 N
5 mm	Stal (~0.2)	0.21 kg / 0.45 pounds 206.0 g / 2.0 N
10 mm	Stal (~0.2)	0.03 kg / 0.07 pounds 30.0 g / 0.3 N
15 mm	Stal (~0.2)	0.01 kg / 0.01 pounds 6.0 g / 0.1 N
20 mm	Stal (~0.2)	0.00 kg / 0.00 pounds 2.0 g / 0.0 N
30 mm	Stal (~0.2)	0.00 kg / 0.00 pounds 0.0 g / 0.0 N
50 mm	Stal (~0.2)	0.00 kg / 0.00 pounds 0.0 g / 0.0 N

The following data presents the estimated force necessary to start the downward movement of the magnet downwards on a vertical steel wall (assuming typical friction). This value is relative to the separation distance between the magnet and the surface.

Table 3: Wall mounting (sliding) - vertical pull
MP 15x7/3.5x5 / N38

Surface type	Friction coefficient / % Mocy	Max load (kg/lbs/g/N)
Raw steel	µ = 0.3 30% Nominalnej Siły	1.53 kg / 3.37 pounds 1527.0 g / 15.0 N
Painted steel (standard)	µ = 0.2 20% Nominalnej Siły	1.02 kg / 2.24 pounds 1018.0 g / 10.0 N
Oily/slippery steel	µ = 0.1 10% Nominalnej Siły	0.51 kg / 1.12 pounds 509.0 g / 5.0 N
Magnet with anti-slip rubber	µ = 0.5 50% Nominalnej Siły	2.55 kg / 5.61 pounds 2545.0 g / 25.0 N

When mounting a element on a vertical wall (e.g., a fridge), it you can count on only about 1/5 of nominal attraction strength. Gravity and a weak degree of grip influence the fact that holders slip faster than they pop off the substrate. Want to create a wall mount? Consider that the shear force is significantly lower than the maximum static pull force. On a slippery surface, the holder will give way down under a significantly smaller cargo. Using a rubber coating can significantly increase the grip.

Table 4: Material efficiency (saturation) - sheet metal selection
MP 15x7/3.5x5 / N38

Steel thickness (mm)	% power	Real pull force (kg/lbs/g/N)
0.5 mm	10%	0.51 kg / 1.12 pounds 509.0 g / 5.0 N
1 mm	25%	1.27 kg / 2.81 pounds 1272.5 g / 12.5 N
2 mm	50%	2.55 kg / 5.61 pounds 2545.0 g / 25.0 N
3 mm	75%	3.82 kg / 8.42 pounds 3817.5 g / 37.4 N
5 mm	100%	5.09 kg / 11.22 pounds 5090.0 g / 49.9 N
10 mm	100%	5.09 kg / 11.22 pounds 5090.0 g / 49.9 N
11 mm	100%	5.09 kg / 11.22 pounds 5090.0 g / 49.9 N
12 mm	100%	5.09 kg / 11.22 pounds 5090.0 g / 49.9 N

A thin sheet is unable to take in the full magnetic flux, which weakens actual performance of the holder. If you install a neodymium to a too thin substrate, the magnetism will penetrate right through and the attraction force will be weaker. To achieve 100% of this neodymium's power, you require a sufficiently solid backing of steel. The material oversaturation causes that on sheet metal structures (e.g., appliance housings), the holder shows lower pull force. We suggest choosing the steel thickness based on the following data.

Table 5: Working in heat (material behavior) - thermal limit
MP 15x7/3.5x5 / N38

Ambient temp. (°C)	Power loss	Remaining pull (kg/lbs/g/N)	Status
20 °C	0.0%	5.09 kg / 11.22 pounds 5090.0 g / 49.9 N	OK
40 °C	-2.2%	4.98 kg / 10.97 pounds 4978.0 g / 48.8 N	OK
60 °C	-4.4%	4.87 kg / 10.73 pounds 4866.0 g / 47.7 N
80 °C	-6.6%	4.75 kg / 10.48 pounds 4754.1 g / 46.6 N
100 °C	-28.8%	3.62 kg / 7.99 pounds 3624.1 g / 35.6 N

Standard neodymium magnets lose parameters above the temperature limit. Protect against heat – high temperature can irreversibly damage this magnet. As the temperature rises, the neodymium's force temporarily decreases. Refrain from using this magnet in hot environments exceeding its safe range. Ignoring the limit will lead to permanent loss of magnetic properties.

*Important note: Thermal stability is determined by both grade, and the Permeance Coefficient Pc. Low-profile magnets (low Pc) risk losing magnetic properties under lower heat stress than taller cylinders. Warning indicator in the table points to a risk of irreversible loss for this specific geometry.

Table 6: Two magnets (attraction) - forces in the system
MP 15x7/3.5x5 / N38

Gap (mm)	Attraction (kg/lbs) (N-S)	Shear Strength (kg/lbs/g/N)	Repulsion (kg/lbs) (N-N)
0 mm	8.17 kg / 18.00 pounds 4 643 Gs	1.22 kg / 2.70 pounds 1225 g / 12.0 N	N/A
1 mm	7.39 kg / 16.29 pounds 5 810 Gs	1.11 kg / 2.44 pounds 1108 g / 10.9 N	6.65 kg / 14.66 pounds ~0 Gs
2 mm	6.55 kg / 14.45 pounds 5 472 Gs	0.98 kg / 2.17 pounds 983 g / 9.6 N	5.90 kg / 13.01 pounds ~0 Gs
3 mm	5.72 kg / 12.62 pounds 5 113 Gs	0.86 kg / 1.89 pounds 858 g / 8.4 N	5.15 kg / 11.35 pounds ~0 Gs
5 mm	4.19 kg / 9.23 pounds 4 374 Gs	0.63 kg / 1.38 pounds 628 g / 6.2 N	3.77 kg / 8.31 pounds ~0 Gs
10 mm	1.66 kg / 3.66 pounds 2 753 Gs	0.25 kg / 0.55 pounds 249 g / 2.4 N	1.49 kg / 3.29 pounds ~0 Gs
20 mm	0.24 kg / 0.54 pounds 1 053 Gs	0.04 kg / 0.08 pounds 36 g / 0.4 N	0.22 kg / 0.48 pounds ~0 Gs
50 mm	0.00 kg / 0.01 pounds 134 Gs	0.00 kg / 0.00 pounds 1 g / 0.0 N	0.00 kg / 0.00 pounds ~0 Gs
60 mm	0.00 kg / 0.00 pounds 83 Gs	0.00 kg / 0.00 pounds 0 g / 0.0 N	0.00 kg / 0.00 pounds ~0 Gs
70 mm	0.00 kg / 0.00 pounds 55 Gs	0.00 kg / 0.00 pounds 0 g / 0.0 N	0.00 kg / 0.00 pounds ~0 Gs
80 mm	0.00 kg / 0.00 pounds 38 Gs	0.00 kg / 0.00 pounds 0 g / 0.0 N	0.00 kg / 0.00 pounds ~0 Gs
90 mm	0.00 kg / 0.00 pounds 27 Gs	0.00 kg / 0.00 pounds 0 g / 0.0 N	0.00 kg / 0.00 pounds ~0 Gs
100 mm	0.00 kg / 0.00 pounds 20 Gs	0.00 kg / 0.00 pounds 0 g / 0.0 N	0.00 kg / 0.00 pounds ~0 Gs

Two magnets interact from a wider radius than a magnet and steel setup. The setup of magnet-to-magnet generates a stronger field and a further horizon of performance. Designing a solid fastener? Utilize two neodymiums instead of one magnet and a steel. Remember that when connecting a pair of magnets, the collision energy is massive. The levitation is marginally weaker than the connection force, but still impressive.
*Field value for N-N configuration is approximately ~0 Gs in the exact middle of the gap (caused by magnetic field nullification).
* Results show friction force of dual same neodymium magnets (friction coefficient ~0.15 for Ni-Ni plating).

Table 7: Hazards (electronics) - precautionary measures
MP 15x7/3.5x5 / N38

Object / Device	Limit (Gauss) / mT	Safe distance
Pacemaker	5 Gs (0.5 mT)	6.5 cm
Hearing aid	10 Gs (1.0 mT)	5.5 cm
Mechanical watch	20 Gs (2.0 mT)	4.0 cm
Phone / Smartphone	40 Gs (4.0 mT)	3.5 cm
Car key	50 Gs (5.0 mT)	3.0 cm
Payment card	400 Gs (40.0 mT)	1.5 cm
HDD hard drive	600 Gs (60.0 mT)	1.0 cm

Powerful magnet radiation is a real danger to IT equipment and pacemakers. These magnets produce a field that destroys function of digital equipment. Remember: the unseen radiation acts through matter and housings. Special caution must be taken by people with hearing aids and drug dispensers. The risk also applies to: mechanical watches, remotes, speakers, and displays. Avoid contact with magnetic cards, hard drives, or sensitive navigation tools.

Table 8: Collisions (cracking risk) - warning
MP 15x7/3.5x5 / N38

Start from (mm)	Speed (km/h)	Energy (J)
10 mm	25.60 km/h (7.11 m/s)	0.16 J
30 mm	25.98 km/h (7.22 m/s)	0.16 J
50 mm	25.98 km/h (7.22 m/s)	0.16 J
100 mm	25.98 km/h (7.22 m/s)	0.16 J

Neodymium magnets are very brittle – a strong collision with metal risks their cracking. Watch the impact speed – a magnet released freely speeds with massive force. Impact energy can cause material chips or dangerous crushing to skin. Be sure to control the product during bringing near metal so it doesn't hit with great force against the metal. A collision at high speed ends with a crack of the magnet. Wear safety glasses when playing with large magnets.

Table 9: Coating parameters (durability)
MP 15x7/3.5x5 / 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 (P_c)
MP 15x7/3.5x5 / N38

Parameter	Value	SI Unit / Description
Magnetic Flux	4 791 Mx	47.9 µWb
P_c Coefficient	0.39	Low (Flat)

Flux value emitted by the pole surface. Key data for generator designers as well as sensors. The P_c coefficient defines the magnet's operating point.

Table 11: Underwater work (magnet fishing)
MP 15x7/3.5x5 / N38

Environment	Effective steel pull	Effect
Air (land)	5.09 kg	Standard
Water (riverbed)	5.83 kg (+0.74 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.

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. Vertical hold

*Note: On a vertical wall, the magnet holds only approx. 20-30% of its nominal pull.

2. Plate thickness effect

*Thin steel (e.g. 0.5mm PC case) significantly weakens 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) = 0.39

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

Engineering data and GPSR

Elemental analysis

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: 030390-2026

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The ring magnet with a hole MP 15x7/3.5x5 / N38 is created for mechanical fastening, where glue might fail or be insufficient. Mounting is clean and reversible, unlike gluing. This product with a force of 5.09 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 great sensitivity. We recommend tightening manually with a screwdriver, not an impact driver, because too much pressure 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.

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. If you must use it outside, paint it with anti-corrosion paint after mounting.

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 Ø15x5 mm and a weight of 6.27 g. The pulling force of this model is an impressive 5.09 kg, which translates to 49.95 N in newtons. The product has a [NiCuNi] coating and is made of NdFeB material. Inner hole dimension: 7/3.5 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.

Pros as well as cons of Nd₂Fe₁₄B magnets.

Strengths

Besides their exceptional strength, neodymium magnets offer the following advantages:

They have stable power, and over nearly ten years their performance decreases symbolically – ~1% (according to theory),
They retain their magnetic properties even under external field action,
By using a shiny layer of nickel, the element presents an aesthetic look,
Neodymium magnets deliver maximum magnetic induction on a small area, which ensures high operational effectiveness,
Due to their durability and thermal resistance, neodymium magnets are capable of operate (depending on the shape) even at high temperatures reaching 230°C or more...
Possibility of custom forming and optimizing to concrete requirements,
Significant place in high-tech industry – they find application in mass storage devices, electric drive systems, medical devices, as well as technologically advanced constructions.
Thanks to efficiency per cm³, small magnets offer high operating force, with minimal size,

Cons

Problematic aspects of neodymium magnets: tips and applications.

Susceptibility to cracking is one of their disadvantages. Upon intense impact they can fracture. We advise keeping them in a special holder, which not only protects them against impacts but also increases their durability
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
Magnets exposed to a humid environment can rust. Therefore when using outdoors, we suggest using water-impermeable magnets made of rubber, plastic or other material resistant to moisture
We suggest casing - magnetic mechanism, due to difficulties in producing threads inside the magnet and complex shapes.
Potential hazard resulting from small fragments of magnets can be dangerous, if swallowed, which gains importance in the context of child health protection. Additionally, small elements of these magnets are able to disrupt the diagnostic process medical after entering the body.
High unit price – neodymium magnets cost more than other types of magnets (e.g. ferrite), which hinders application in large quantities

Holding force characteristics

Highest magnetic holding force – what it depends on?

Information about lifting capacity is the result of a measurement for optimal configuration, including:

on a plate made of mild steel, effectively closing the magnetic flux
possessing a thickness of at least 10 mm to ensure full flux closure
with an polished touching surface
under conditions of gap-free contact (metal-to-metal)
for force applied at a right angle (pull-off, not shear)
at temperature room level

Lifting capacity in real conditions – factors

Holding efficiency impacted by specific conditions, mainly (from most important):

Gap between surfaces – every millimeter of separation (caused e.g. by veneer or unevenness) diminishes the pulling force, often by half at just 0.5 mm.
Load vector – maximum parameter is reached only during pulling at a 90° angle. The force required to slide of the magnet along the surface is typically many times lower (approx. 1/5 of the lifting capacity).
Wall thickness – thin material does not allow full use of the magnet. Part of the magnetic field passes through the material instead of generating force.
Material composition – not every steel attracts identically. Alloy additives weaken the interaction with the magnet.
Surface structure – the smoother and more polished the surface, the better the adhesion and stronger the hold. Roughness creates an air distance.
Thermal conditions – NdFeB sinters have a sensitivity to temperature. At higher temperatures they are weaker, and in frost gain strength (up to a certain limit).

Lifting capacity testing was performed on a smooth plate of optimal thickness, under a perpendicular pulling force, whereas under attempts to slide the magnet the load capacity is reduced by as much as 5 times. In addition, even a minimal clearance between the magnet’s surface and the plate decreases the holding force.

H&S for magnets

Thermal limits

Control the heat. Exposing the magnet above 80 degrees Celsius will permanently weaken its magnetic structure and strength.

Cards and drives

Data protection: Strong magnets can ruin payment cards and delicate electronics (heart implants, hearing aids, timepieces).

Compass and GPS

A strong magnetic field negatively affects the functioning of compasses in phones and GPS navigation. Do not bring magnets near a smartphone to prevent damaging the sensors.

Bodily injuries

Large magnets can break fingers in a fraction of a second. Under no circumstances put your hand betwixt two attracting surfaces.

Do not give to children

Always keep magnets out of reach of children. Ingestion danger is high, and the consequences of magnets clamping inside the body are fatal.

Eye protection

Beware of splinters. Magnets can explode upon violent connection, ejecting sharp fragments into the air. Eye protection is mandatory.

Flammability

Dust generated during machining of magnets is flammable. Do not drill into magnets without proper cooling and knowledge.

Allergy Warning

Studies show that the nickel plating (standard magnet coating) is a strong allergen. If you have an allergy, refrain from direct skin contact or select versions in plastic housing.

Do not underestimate power

Use magnets with awareness. Their huge power can surprise even experienced users. Be vigilant and respect their force.

ICD Warning

Warning for patients: Powerful magnets affect electronics. Keep at least 30 cm distance or request help to work with the magnets.

Danger! Details about risks in the article: Safety of working with magnets.

MP 15x7/3.5x5 / N38 - ring magnet

Technical details - MP 15x7/3.5x5 / N38 - ring magnet

Magnetic properties of material N38

Physical properties of sintered neodymium magnets Nd2Fe14B at 20°C

Engineering simulation of the magnet - data

Table 1: Static pull force (force vs distance) - power drop MP 15x7/3.5x5 / N38

Table 2: Slippage hold (wall) MP 15x7/3.5x5 / N38

Table 3: Wall mounting (sliding) - vertical pull MP 15x7/3.5x5 / N38

Table 4: Material efficiency (saturation) - sheet metal selection MP 15x7/3.5x5 / N38

Table 5: Working in heat (material behavior) - thermal limit MP 15x7/3.5x5 / N38

Table 6: Two magnets (attraction) - forces in the system MP 15x7/3.5x5 / N38

Table 7: Hazards (electronics) - precautionary measures MP 15x7/3.5x5 / N38

Table 8: Collisions (cracking risk) - warning MP 15x7/3.5x5 / N38

Table 9: Coating parameters (durability) MP 15x7/3.5x5 / N38

Table 10: Electrical data (Pc) MP 15x7/3.5x5 / N38

Table 11: Underwater work (magnet fishing) MP 15x7/3.5x5 / N38

1. Vertical hold

2. Plate thickness effect

3. Power loss vs temp

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

Elemental analysis

Ecology and recycling (GPSR)

Magnet pull force

Magnetic Induction

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Pros as well as cons of Nd2Fe14B magnets.

Strengths

Cons

Holding force characteristics

Highest magnetic holding force – what it depends on?

Lifting capacity in real conditions – factors

H&S for magnets

Thermal limits

Cards and drives

Compass and GPS

Bodily injuries

Do not give to children

Eye protection

Flammability

Allergy Warning

Do not underestimate power

ICD Warning

Physical properties of sintered neodymium magnets Nd₂Fe₁₄B at 20°C

Table 1: Static pull force (force vs distance) - power drop
MP 15x7/3.5x5 / N38

Table 2: Slippage hold (wall)
MP 15x7/3.5x5 / N38

Table 3: Wall mounting (sliding) - vertical pull
MP 15x7/3.5x5 / N38

Table 4: Material efficiency (saturation) - sheet metal selection
MP 15x7/3.5x5 / N38

Table 5: Working in heat (material behavior) - thermal limit
MP 15x7/3.5x5 / N38

Table 6: Two magnets (attraction) - forces in the system
MP 15x7/3.5x5 / N38

Table 7: Hazards (electronics) - precautionary measures
MP 15x7/3.5x5 / N38

Table 8: Collisions (cracking risk) - warning
MP 15x7/3.5x5 / N38

Table 9: Coating parameters (durability)
MP 15x7/3.5x5 / N38

Table 10: Electrical data (P_c)
MP 15x7/3.5x5 / N38

Table 11: Underwater work (magnet fishing)
MP 15x7/3.5x5 / N38

Pros as well as cons of Nd₂Fe₁₄B magnets.