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MW 8x4 / N38 - cylindrical magnet

cylindrical magnet

Catalog no 010104

GTIN/EAN: 5906301811039

5.00
Load capacity 2.04 kg / 20.00 N Magnetic Induction 437.78 mT / 4378 Gs
Diameter Ø
8 mm [±0,1 mm]
Height
4 mm [±0,1 mm]
Weight
1.51 g
Magnetization Direction
↑ axial
Coating
[NiCuNi] Nickel

How we measure these parameters — certificates and measurements

0.570net / pcs

0.701 zł with VAT (23% VAT) / pcs

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price from 1 pcs
0.570 zł
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price from 875 pcs
0.513 zł
0.631 zł
price from 1750 pcs
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0.617 zł

Frequently asked questions

What is the maximum working temperature of a disc magnet?
Standard N-series grades work up to 80 °C. Grades N50, N52 and N54 have a lower limit of 60 °C, because coercivity falls as BHmax rises. Higher temperatures require the H (120 °C), SH (150 °C), UH (180 °C), EH (200 °C) or AH (230 °C) series. Within the working range the magnet loses about 0.11% of its induction per degree, and that loss is reversible.
What is the difference between N38, N42 and N52?
The number after N is the energy product BHmax. Moving from N38 to N52 raises it by several tens of percent, but the real holding force increases by roughly 20%, because force also depends on geometry and on the magnetic circuit. N52 costs about twice as much as N42, so for most mounting work N38–N42 is the best price-to-force ratio.
What is the dimensional tolerance?
±0.1 mm as standard, ±0.05 mm to order. The tolerance is stated next to the dimensions on every product page.

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.

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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 specification of the product - MW 8x4 / N38 - cylindrical magnet

Specification / characteristics - MW 8x4 / N38 - cylindrical magnet

properties
properties values
Cat. no. 010104
GTIN/EAN 5906301811039
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 Ø 8 mm [±0,1 mm]
Height 4 mm [±0,1 mm]
Weight 1.51 g
Magnetization Direction ↑ axial
Load capacity ~ ? 2.04 kg / 20.00 N
Magnetic Induction ~ ? 437.78 mT / 4378 Gs
Coating [NiCuNi] Nickel
Manufacturing Tolerance ±0.1 mm

Magnetic properties of material N38

Specification / characteristics MW 8x4 / N38 - cylindrical magnet
properties values units
Remanence Br ? 12.2-12.6 kGs
Remanence Br ? 1220-1260 mT
Coercivity bHc ? 10.8-11.5 kOe
Coercivity bHc ? 860-915 kA/m
Intrinsic coercivity iHc ≥ 12 kOe
Intrinsic coercivity iHc ≥ 955 kA/m
Energy product BHmax ? 36-38 BH max MGOe
Energy product BHmax ? 287-303 BH max KJ/m
Maximum working temperature ? ≤ 80 °C

Physical properties of sintered neodymium magnets Nd2Fe14B at 20°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 assembly - report

The following information represent the result of a mathematical simulation. Results are based on algorithms for the material Nd2Fe14B. Actual parameters may deviate from the simulation results. Please consider these calculations as a reference point when designing systems.

Table 1: Static force (pull vs gap) - power drop
MW 8x4 / N38

Distance (mm) Induction (Gauss) / mT Pull Force (kg/lbs/g/N) Risk Status
0 mm 4374 Gs
437.4 mT
2.04 kg / 4.50 pounds
2040.0 g / 20.0 N
strong
1 mm 3338 Gs
333.8 mT
1.19 kg / 2.62 pounds
1187.8 g / 11.7 N
weak grip
2 mm 2386 Gs
238.6 mT
0.61 kg / 1.34 pounds
607.0 g / 6.0 N
weak grip
3 mm 1663 Gs
166.3 mT
0.29 kg / 0.65 pounds
294.9 g / 2.9 N
weak grip
5 mm 824 Gs
82.4 mT
0.07 kg / 0.16 pounds
72.4 g / 0.7 N
weak grip
10 mm 205 Gs
20.5 mT
0.00 kg / 0.01 pounds
4.5 g / 0.0 N
weak grip
15 mm 76 Gs
7.6 mT
0.00 kg / 0.00 pounds
0.6 g / 0.0 N
weak grip
20 mm 36 Gs
3.6 mT
0.00 kg / 0.00 pounds
0.1 g / 0.0 N
weak grip
30 mm 12 Gs
1.2 mT
0.00 kg / 0.00 pounds
0.0 g / 0.0 N
weak grip
50 mm 3 Gs
0.3 mT
0.00 kg / 0.00 pounds
0.0 g / 0.0 N
weak grip

Table 2: Sliding hold (wall)
MW 8x4 / N38

Distance (mm) Friction coefficient Pull Force (kg/lbs/g/N)
0 mm Stal (~0.2) 0.41 kg / 0.90 pounds
408.0 g / 4.0 N
1 mm Stal (~0.2) 0.24 kg / 0.52 pounds
238.0 g / 2.3 N
2 mm Stal (~0.2) 0.12 kg / 0.27 pounds
122.0 g / 1.2 N
3 mm Stal (~0.2) 0.06 kg / 0.13 pounds
58.0 g / 0.6 N
5 mm Stal (~0.2) 0.01 kg / 0.03 pounds
14.0 g / 0.1 N
10 mm Stal (~0.2) 0.00 kg / 0.00 pounds
0.0 g / 0.0 N
15 mm Stal (~0.2) 0.00 kg / 0.00 pounds
0.0 g / 0.0 N
20 mm Stal (~0.2) 0.00 kg / 0.00 pounds
0.0 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

Table 3: Vertical assembly (sliding) - behavior on slippery surfaces
MW 8x4 / N38

Surface type Friction coefficient / % Mocy Max load (kg/lbs/g/N)
Raw steel
µ = 0.3 30% Nominalnej Siły
0.61 kg / 1.35 pounds
612.0 g / 6.0 N
Painted steel (standard)
µ = 0.2 20% Nominalnej Siły
0.41 kg / 0.90 pounds
408.0 g / 4.0 N
Oily/slippery steel
µ = 0.1 10% Nominalnej Siły
0.20 kg / 0.45 pounds
204.0 g / 2.0 N
Magnet with anti-slip rubber
µ = 0.5 50% Nominalnej Siły
1.02 kg / 2.25 pounds
1020.0 g / 10.0 N

Table 4: Steel thickness (substrate influence) - sheet metal selection
MW 8x4 / N38

Steel thickness (mm) % power Real pull force (kg/lbs/g/N)
0.5 mm
10%
0.20 kg / 0.45 pounds
204.0 g / 2.0 N
1 mm
25%
0.51 kg / 1.12 pounds
510.0 g / 5.0 N
2 mm
50%
1.02 kg / 2.25 pounds
1020.0 g / 10.0 N
3 mm
75%
1.53 kg / 3.37 pounds
1530.0 g / 15.0 N
5 mm
100%
2.04 kg / 4.50 pounds
2040.0 g / 20.0 N
10 mm
100%
2.04 kg / 4.50 pounds
2040.0 g / 20.0 N
11 mm
100%
2.04 kg / 4.50 pounds
2040.0 g / 20.0 N
12 mm
100%
2.04 kg / 4.50 pounds
2040.0 g / 20.0 N

Table 5: Working in heat (material behavior) - thermal limit
MW 8x4 / N38

Ambient temp. (°C) Power loss Remaining pull (kg/lbs/g/N) Status
20 °C 0.0% 2.04 kg / 4.50 pounds
2040.0 g / 20.0 N
OK
40 °C -2.2% 2.00 kg / 4.40 pounds
1995.1 g / 19.6 N
OK
60 °C -4.4% 1.95 kg / 4.30 pounds
1950.2 g / 19.1 N
80 °C -6.6% 1.91 kg / 4.20 pounds
1905.4 g / 18.7 N
100 °C -28.8% 1.45 kg / 3.20 pounds
1452.5 g / 14.2 N

Table 6: Two magnets (attraction) - field collision
MW 8x4 / N38

Gap (mm) Attraction (kg/lbs) (N-S) Lateral Force (kg/lbs/g/N) Repulsion (kg/lbs) (N-N)
0 mm 5.93 kg / 13.07 pounds
5 531 Gs
0.89 kg / 1.96 pounds
889 g / 8.7 N
N/A
1 mm 4.63 kg / 10.21 pounds
7 730 Gs
0.69 kg / 1.53 pounds
694 g / 6.8 N
4.17 kg / 9.18 pounds
~0 Gs
2 mm 3.45 kg / 7.61 pounds
6 675 Gs
0.52 kg / 1.14 pounds
518 g / 5.1 N
3.11 kg / 6.85 pounds
~0 Gs
3 mm 2.49 kg / 5.50 pounds
5 674 Gs
0.37 kg / 0.82 pounds
374 g / 3.7 N
2.25 kg / 4.95 pounds
~0 Gs
5 mm 1.23 kg / 2.72 pounds
3 989 Gs
0.18 kg / 0.41 pounds
185 g / 1.8 N
1.11 kg / 2.45 pounds
~0 Gs
10 mm 0.21 kg / 0.46 pounds
1 648 Gs
0.03 kg / 0.07 pounds
32 g / 0.3 N
0.19 kg / 0.42 pounds
~0 Gs
20 mm 0.01 kg / 0.03 pounds
410 Gs
0.00 kg / 0.00 pounds
2 g / 0.0 N
0.01 kg / 0.03 pounds
~0 Gs
50 mm 0.00 kg / 0.00 pounds
39 Gs
0.00 kg / 0.00 pounds
0 g / 0.0 N
0.00 kg / 0.00 pounds
~0 Gs
60 mm 0.00 kg / 0.00 pounds
24 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
15 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
11 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
8 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
6 Gs
0.00 kg / 0.00 pounds
0 g / 0.0 N
0.00 kg / 0.00 pounds
~0 Gs

Table 7: Safety (HSE) (electronics) - warnings
MW 8x4 / N38

Object / Device Limit (Gauss) / mT Safe distance
Pacemaker 5 Gs (0.5 mT) 4.5 cm
Hearing aid 10 Gs (1.0 mT) 3.5 cm
Timepiece 20 Gs (2.0 mT) 2.5 cm
Mobile device 40 Gs (4.0 mT) 2.0 cm
Car key 50 Gs (5.0 mT) 2.0 cm
Payment card 400 Gs (40.0 mT) 1.0 cm
HDD hard drive 600 Gs (60.0 mT) 1.0 cm

Table 8: Collisions (kinetic energy) - warning
MW 8x4 / N38

Start from (mm) Speed (km/h) Energy (J) Predicted outcome
10 mm 23.69 km/h
(6.58 m/s)
0.03 J
30 mm 23.73 km/h
(6.59 m/s)
0.03 J
50 mm 23.73 km/h
(6.59 m/s)
0.03 J
100 mm 23.73 km/h
(6.59 m/s)
0.03 J

Table 9: Coating parameters (durability)
MW 8x4 / 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)

Table 10: Electrical data (Pc)
MW 8x4 / N38

Parameter Value SI Unit / Description
Magnetic Flux 2 233 Mx 22.3 µWb
Pc Coefficient 0.59 Low (Flat)

Table 11: Underwater work (magnet fishing)
MW 8x4 / N38

Environment Effective steel pull Effect
Air (land) 2.04 kg Standard
Water (riverbed) 2.34 kg
(+0.30 kg buoyancy gain)
+14.5%
Warning: Standard nickel requires drying after every contact with moisture; lack of maintenance will lead to rust spots.

1. Wall mount (shear)

*Caution: On a vertical surface, the magnet retains just a fraction of its nominal pull.

2. Plate thickness effect

*Thin steel (e.g. 0.5mm PC case) significantly limits the holding force.

3. Temperature resistance

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

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

chart generated for the permeance coefficient Pc (Permeance Coefficient) = 0.59

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 Pc (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 Pc 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

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%

Sustainability

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: 010104-2026
Measurement Calculator

Pulling force


Magnetic Field

Other proposals

The offered product is an incredibly powerful cylindrical magnet, made from durable NdFeB material, which, with dimensions of Ø8x4 mm, guarantees optimal power. This specific item boasts an accuracy of ±0.1mm and industrial build quality, making it a perfect solution for professional engineers and designers. As a magnetic rod with significant force (approx. 2.04 kg), this product is in stock from our warehouse in Poland, ensuring lightning-fast order fulfillment. Moreover, its Ni-Cu-Ni coating effectively protects it against corrosion in typical operating conditions, guaranteeing an aesthetic appearance and durability for years.
This model is perfect for building electric motors, advanced sensors, and efficient magnetic separators, where field concentration on a small surface counts. Thanks to the pull force of 20.00 N with a weight of only 1.51 g, this cylindrical magnet is indispensable in miniature devices and wherever low weight is crucial.
Due to the brittleness of the NdFeB material, we absolutely advise against force-fitting (so-called press-fit), as this risks chipping the coating of this precision component. To ensure long-term durability in industry, specialized industrial adhesives are used, which are safe for nickel and fill the gap, guaranteeing durability of the connection.
Grade N38 is the most popular standard for industrial neodymium magnets, offering a great economic balance and operational stability. If you need even stronger magnets in the same volume (Ø8x4), contact us regarding higher grades (e.g., N50, N52), however, N38 is the standard in continuous sale in our store.
This model is characterized by dimensions Ø8x4 mm, which, at a weight of 1.51 g, makes it an element with high magnetic energy density. The value of 20.00 N means that the magnet is capable of holding a weight many times exceeding its own mass of 1.51 g. The product has a [NiCuNi] coating, which protects the surface against external factors, giving it an aesthetic, silvery shine.
Standardly, the magnetic axis runs through the center of the cylinder, causing the greatest attraction force to occur on the bases with a diameter of 8 mm. Thanks to this, the magnet can be easily glued into a hole and achieve a strong field on the front surface. On request, we can also produce versions magnetized diametrically if your project requires it.

Pros and cons of rare earth magnets.

Benefits

Besides their durability, neodymium magnets are valued for these benefits:
  • They retain attractive force for nearly 10 years – the loss is just ~1% (based on simulations),
  • They maintain their magnetic properties even under external field action,
  • By applying a decorative coating of silver, the element has an modern look,
  • The surface of neodymium magnets generates a intense magnetic field – this is one of their assets,
  • Thanks to resistance to high temperature, they are able to function (depending on the form) even at temperatures up to 230°C and higher...
  • Thanks to versatility in designing and the ability to adapt to client solutions,
  • Universal use in modern industrial fields – they find application in magnetic memories, electromotive mechanisms, medical equipment, and complex engineering applications.
  • Thanks to their power density, small magnets offer high operating force, occupying minimum space,

Limitations

Disadvantages of neodymium magnets:
  • To avoid cracks upon strong impacts, we recommend using special steel holders. Such a solution protects the magnet and simultaneously increases its durability.
  • NdFeB magnets lose power when exposed to high temperatures. After reaching 80°C, many of them experience permanent weakening of strength (a factor is the shape and dimensions of the magnet). We offer magnets specially adapted to work at temperatures up to 230°C marked [AH], which are extremely resistant to heat
  • When exposed to humidity, magnets start to rust. For applications outside, it is recommended to use protective magnets, such as those in rubber or plastics, which secure oxidation as well as corrosion.
  • Due to limitations in creating threads and complicated shapes in magnets, we propose using a housing - magnetic mechanism.
  • Potential hazard to health – tiny shards of magnets pose a threat, when accidentally swallowed, which becomes key in the aspect of protecting the youngest. Additionally, small elements of these devices can be problematic in diagnostics medical in case of swallowing.
  • Due to expensive raw materials, their price exceeds standard values,

Pull force analysis

Highest magnetic holding forcewhat it depends on?

Breakaway force is the result of a measurement for ideal contact conditions, including:
  • on a base made of structural steel, optimally conducting the magnetic field
  • with a cross-section of at least 10 mm
  • with a surface free of scratches
  • without any insulating layer between the magnet and steel
  • under axial force direction (90-degree angle)
  • at temperature approx. 20 degrees Celsius

Lifting capacity in real conditions – factors

In practice, the actual lifting capacity depends on many variables, listed from most significant:
  • Space between surfaces – even a fraction of a millimeter of separation (caused e.g. by varnish or unevenness) diminishes the magnet efficiency, often by half at just 0.5 mm.
  • Force direction – remember that the magnet has greatest strength perpendicularly. Under sliding down, the holding force drops significantly, often to levels of 20-30% of the maximum value.
  • Plate thickness – insufficiently thick sheet does not accept the full field, causing part of the power to be lost into the air.
  • Chemical composition of the base – low-carbon steel gives the best results. Alloy admixtures lower magnetic properties and lifting capacity.
  • Surface structure – the more even the surface, the better the adhesion and stronger the hold. Unevenness acts like micro-gaps.
  • Temperature influence – high temperature reduces magnetic field. Exceeding the limit temperature can permanently damage the magnet.

Holding force was measured on a smooth steel plate of 20 mm thickness, when the force acted perpendicularly, 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 and the plate reduces the load capacity.

H&S for magnets
Precision electronics

Note: rare earth magnets generate a field that confuses precision electronics. Keep a separation from your phone, device, and navigation systems.

Allergy Warning

It is widely known that nickel (standard magnet coating) is a common allergen. For allergy sufferers, prevent touching magnets with bare hands or opt for coated magnets.

Dust explosion hazard

Fire warning: Rare earth powder is highly flammable. Avoid machining magnets without safety gear as this may cause fire.

Operating temperature

Monitor thermal conditions. Exposing the magnet above 80 degrees Celsius will ruin its properties and pulling force.

Keep away from computers

Equipment safety: Neodymium magnets can ruin data carriers and delicate electronics (heart implants, hearing aids, mechanical watches).

ICD Warning

For implant holders: Powerful magnets disrupt electronics. Maintain at least 30 cm distance or request help to work with the magnets.

Magnet fragility

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

Crushing force

Large magnets can crush fingers instantly. Under no circumstances place your hand between two attracting surfaces.

Adults only

Strictly keep magnets away from children. Risk of swallowing is high, and the effects of magnets connecting inside the body are tragic.

Do not underestimate power

Before use, read the rules. Uncontrolled attraction can break the magnet or injure your hand. Think ahead.

Safety First! Need more info? Read our article: Why are neodymium magnets dangerous?