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MP 30x6x10 / N38 - ring magnet

ring magnet

Catalog no 030197

GTIN/EAN: 5906301812142

5.00

Diameter

30 mm [±0,1 mm]

internal diameter Ø

6 mm [±0,1 mm]

Height

10 mm [±0,1 mm]

Weight

50.89 g

Magnetization Direction

↑ axial

Load capacity

20.71 kg / 203.16 N

Magnetic Induction

343.81 mT / 3438 Gs

Coating

[NiCuNi] Nickel

16.00 with VAT / pcs + price for transport

13.01 ZŁ net + 23% VAT / pcs

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Technical details - MP 30x6x10 / N38 - ring magnet

Specification / characteristics - MP 30x6x10 / N38 - ring magnet

properties
properties values
Cat. no. 030197
GTIN/EAN 5906301812142
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 30 mm [±0,1 mm]
internal diameter Ø 6 mm [±0,1 mm]
Height 10 mm [±0,1 mm]
Weight 50.89 g
Magnetization Direction ↑ axial
Load capacity ~ ? 20.71 kg / 203.16 N
Magnetic Induction ~ ? 343.81 mT / 3438 Gs
Coating [NiCuNi] Nickel
Manufacturing Tolerance ±0.1 mm

Magnetic properties of material N38

Specification / characteristics MP 30x6x10 / 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

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

Technical analysis of the magnet - technical parameters

These information are the outcome of a engineering calculation. Results were calculated on algorithms for the class Nd2Fe14B. Real-world performance might slightly differ from theoretical values. Treat these data as a reference point during assembly planning.

Table 1: Static force (force vs gap) - characteristics
MP 30x6x10 / N38

Distance (mm) Induction (Gauss) / mT Pull Force (kg/lbs/g/N) Risk Status
0 mm 5619 Gs
561.9 mT
20.71 kg / 45.66 pounds
20710.0 g / 203.2 N
crushing
1 mm 5241 Gs
524.1 mT
18.01 kg / 39.71 pounds
18011.7 g / 176.7 N
crushing
2 mm 4861 Gs
486.1 mT
15.50 kg / 34.17 pounds
15498.1 g / 152.0 N
crushing
3 mm 4490 Gs
449.0 mT
13.22 kg / 29.15 pounds
13223.5 g / 129.7 N
crushing
5 mm 3792 Gs
379.2 mT
9.43 kg / 20.79 pounds
9429.0 g / 92.5 N
warning
10 mm 2404 Gs
240.4 mT
3.79 kg / 8.36 pounds
3791.3 g / 37.2 N
warning
15 mm 1526 Gs
152.6 mT
1.53 kg / 3.37 pounds
1527.0 g / 15.0 N
low risk
20 mm 1000 Gs
100.0 mT
0.66 kg / 1.45 pounds
655.5 g / 6.4 N
low risk
30 mm 482 Gs
48.2 mT
0.15 kg / 0.34 pounds
152.6 g / 1.5 N
low risk
50 mm 161 Gs
16.1 mT
0.02 kg / 0.04 pounds
17.0 g / 0.2 N
low risk

Table 2: Vertical force (vertical surface)
MP 30x6x10 / N38

Distance (mm) Friction coefficient Pull Force (kg/lbs/g/N)
0 mm Stal (~0.2) 4.14 kg / 9.13 pounds
4142.0 g / 40.6 N
1 mm Stal (~0.2) 3.60 kg / 7.94 pounds
3602.0 g / 35.3 N
2 mm Stal (~0.2) 3.10 kg / 6.83 pounds
3100.0 g / 30.4 N
3 mm Stal (~0.2) 2.64 kg / 5.83 pounds
2644.0 g / 25.9 N
5 mm Stal (~0.2) 1.89 kg / 4.16 pounds
1886.0 g / 18.5 N
10 mm Stal (~0.2) 0.76 kg / 1.67 pounds
758.0 g / 7.4 N
15 mm Stal (~0.2) 0.31 kg / 0.67 pounds
306.0 g / 3.0 N
20 mm Stal (~0.2) 0.13 kg / 0.29 pounds
132.0 g / 1.3 N
30 mm Stal (~0.2) 0.03 kg / 0.07 pounds
30.0 g / 0.3 N
50 mm Stal (~0.2) 0.00 kg / 0.01 pounds
4.0 g / 0.0 N

Table 3: Vertical assembly (sliding) - behavior on slippery surfaces
MP 30x6x10 / N38

Surface type Friction coefficient / % Mocy Max load (kg/lbs/g/N)
Raw steel
µ = 0.3 30% Nominalnej Siły
6.21 kg / 13.70 pounds
6213.0 g / 60.9 N
Painted steel (standard)
µ = 0.2 20% Nominalnej Siły
4.14 kg / 9.13 pounds
4142.0 g / 40.6 N
Oily/slippery steel
µ = 0.1 10% Nominalnej Siły
2.07 kg / 4.57 pounds
2071.0 g / 20.3 N
Magnet with anti-slip rubber
µ = 0.5 50% Nominalnej Siły
10.36 kg / 22.83 pounds
10355.0 g / 101.6 N

Table 4: Material efficiency (saturation) - power losses
MP 30x6x10 / N38

Steel thickness (mm) % power Real pull force (kg/lbs/g/N)
0.5 mm
5%
1.04 kg / 2.28 pounds
1035.5 g / 10.2 N
1 mm
13%
2.59 kg / 5.71 pounds
2588.8 g / 25.4 N
2 mm
25%
5.18 kg / 11.41 pounds
5177.5 g / 50.8 N
3 mm
38%
7.77 kg / 17.12 pounds
7766.3 g / 76.2 N
5 mm
63%
12.94 kg / 28.54 pounds
12943.8 g / 127.0 N
10 mm
100%
20.71 kg / 45.66 pounds
20710.0 g / 203.2 N
11 mm
100%
20.71 kg / 45.66 pounds
20710.0 g / 203.2 N
12 mm
100%
20.71 kg / 45.66 pounds
20710.0 g / 203.2 N

Table 5: Thermal resistance (stability) - resistance threshold
MP 30x6x10 / N38

Ambient temp. (°C) Power loss Remaining pull (kg/lbs/g/N) Status
20 °C 0.0% 20.71 kg / 45.66 pounds
20710.0 g / 203.2 N
OK
40 °C -2.2% 20.25 kg / 44.65 pounds
20254.4 g / 198.7 N
OK
60 °C -4.4% 19.80 kg / 43.65 pounds
19798.8 g / 194.2 N
OK
80 °C -6.6% 19.34 kg / 42.64 pounds
19343.1 g / 189.8 N
100 °C -28.8% 14.75 kg / 32.51 pounds
14745.5 g / 144.7 N

Table 6: Magnet-Magnet interaction (repulsion) - forces in the system
MP 30x6x10 / N38

Gap (mm) Attraction (kg/lbs) (N-S) Shear Force (kg/lbs/g/N) Repulsion (kg/lbs) (N-N)
0 mm 103.97 kg / 229.22 pounds
6 035 Gs
15.60 kg / 34.38 pounds
15596 g / 153.0 N
N/A
1 mm 97.15 kg / 214.17 pounds
10 864 Gs
14.57 kg / 32.13 pounds
14572 g / 143.0 N
87.43 kg / 192.75 pounds
~0 Gs
2 mm 90.42 kg / 199.35 pounds
10 481 Gs
13.56 kg / 29.90 pounds
13564 g / 133.1 N
81.38 kg / 179.42 pounds
~0 Gs
3 mm 83.97 kg / 185.13 pounds
10 100 Gs
12.60 kg / 27.77 pounds
12596 g / 123.6 N
75.57 kg / 166.61 pounds
~0 Gs
5 mm 71.94 kg / 158.60 pounds
9 349 Gs
10.79 kg / 23.79 pounds
10791 g / 105.9 N
64.75 kg / 142.74 pounds
~0 Gs
10 mm 47.34 kg / 104.36 pounds
7 583 Gs
7.10 kg / 15.65 pounds
7100 g / 69.7 N
42.60 kg / 93.92 pounds
~0 Gs
20 mm 19.03 kg / 41.96 pounds
4 809 Gs
2.86 kg / 6.29 pounds
2855 g / 28.0 N
17.13 kg / 37.77 pounds
~0 Gs
50 mm 1.53 kg / 3.37 pounds
1 363 Gs
0.23 kg / 0.51 pounds
229 g / 2.2 N
1.38 kg / 3.03 pounds
~0 Gs
60 mm 0.77 kg / 1.69 pounds
965 Gs
0.11 kg / 0.25 pounds
115 g / 1.1 N
0.69 kg / 1.52 pounds
~0 Gs
70 mm 0.41 kg / 0.90 pounds
706 Gs
0.06 kg / 0.14 pounds
61 g / 0.6 N
0.37 kg / 0.81 pounds
~0 Gs
80 mm 0.23 kg / 0.51 pounds
531 Gs
0.03 kg / 0.08 pounds
35 g / 0.3 N
0.21 kg / 0.46 pounds
~0 Gs
90 mm 0.14 kg / 0.30 pounds
409 Gs
0.02 kg / 0.05 pounds
21 g / 0.2 N
0.12 kg / 0.27 pounds
~0 Gs
100 mm 0.09 kg / 0.19 pounds
322 Gs
0.01 kg / 0.03 pounds
13 g / 0.1 N
0.08 kg / 0.17 pounds
~0 Gs

Table 7: Hazards (implants) - precautionary measures
MP 30x6x10 / N38

Object / Device Limit (Gauss) / mT Safe distance
Pacemaker 5 Gs (0.5 mT) 19.5 cm
Hearing aid 10 Gs (1.0 mT) 15.0 cm
Timepiece 20 Gs (2.0 mT) 12.0 cm
Phone / Smartphone 40 Gs (4.0 mT) 9.0 cm
Remote 50 Gs (5.0 mT) 8.5 cm
Payment card 400 Gs (40.0 mT) 3.5 cm
HDD hard drive 600 Gs (60.0 mT) 3.0 cm

Table 8: Collisions (kinetic energy) - warning
MP 30x6x10 / N38

Start from (mm) Speed (km/h) Energy (J) Predicted outcome
10 mm 22.55 km/h
(6.26 m/s)
1.00 J
30 mm 35.40 km/h
(9.83 m/s)
2.46 J
50 mm 45.52 km/h
(12.64 m/s)
4.07 J
100 mm 64.34 km/h
(17.87 m/s)
8.13 J

Table 9: Coating parameters (durability)
MP 30x6x10 / 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 (Flux)
MP 30x6x10 / N38

Parameter Value SI Unit / Description
Magnetic Flux 31 585 Mx 315.8 µWb
Pc Coefficient 0.96 High (Stable)

Table 11: Submerged application
MP 30x6x10 / N38

Environment Effective steel pull Effect
Air (land) 20.71 kg Standard
Water (riverbed) 23.71 kg
(+3.00 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.
1. Wall mount (shear)

*Warning: On a vertical surface, the magnet holds only a fraction of its max power.

2. Steel thickness impact

*Thin steel (e.g. computer case) significantly reduces the holding force.

3. Heat tolerance

*For N38 material, the max working temp is 80°C.

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

chart generated for the permeance coefficient Pc (Permeance Coefficient) = 0.96

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 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.

Technical specification and ecology
Material specification
iron (Fe) 64% – 68%
neodymium (Nd) 29% – 32%
boron (B) 1.1% – 1.2%
dysprosium (Dy) 0.5% – 2.0%
coating (Ni-Cu-Ni) < 0.05%
Ecology and recycling (GPSR)
recyclability (EoL) 100%
recycled raw materials ~10% (pre-cons)
carbon footprint low / zredukowany
waste code (EWC) 16 02 16
Safety card (GPSR)
responsible entity
Dhit sp. z o.o.
ul. Kościuszki 6A, 05-850 Ożarów Mazowiecki
tel: +48 22 499 98 98 | e-mail: bok@dhit.pl
batch number/type
id: 030197-2026
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Magnet pull force

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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. Mounting is clean and reversible, unlike gluing. 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 30x6x10 / N38. Neodymium magnets are sintered ceramics, which means they are hard but breakable and inelastic. One turn too many can destroy the magnet, so do it slowly. The flat screw head should evenly press the magnet. 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. In the place of the mounting hole, the coating is thinner and can be damaged when tightening the screw, which will become a corrosion focus. If you must use it outside, paint it with anti-corrosion paint after mounting.
A screw or bolt with a thread diameter smaller than 6 mm fits this model. For magnets with a straight hole, a conical head can act like a wedge and burst the magnet. Aesthetic mounting requires selecting the appropriate head size.
The presented product is a ring magnet with dimensions Ø30 mm (outer diameter) and height 10 mm. The key parameter here is the lifting capacity amounting to approximately 20.71 kg (force ~203.16 N). The product has a [NiCuNi] coating and is made of NdFeB material. Inner hole dimension: 6 mm.
The poles are located on the planes with holes, not on the sides of the ring. If you want two such magnets screwed with cones facing each other (faces) to attract, you must connect them with opposite poles (N to S). When ordering a larger quantity, magnets are usually packed in stacks, where they are already naturally paired.

Pros and cons of neodymium magnets.

Benefits

Besides their exceptional pulling force, neodymium magnets offer the following advantages:
  • Their strength remains stable, and after around 10 years it drops only by ~1% (theoretically),
  • They have excellent resistance to weakening of magnetic properties as a result of external magnetic sources,
  • The use of an refined coating of noble metals (nickel, gold, silver) causes the element to have aesthetics,
  • The surface of neodymium magnets generates a powerful magnetic field – this is a distinguishing feature,
  • Thanks to resistance to high temperature, they can operate (depending on the form) even at temperatures up to 230°C and higher...
  • Due to the possibility of flexible forming and customization to custom requirements, NdFeB magnets can be modeled in a wide range of forms and dimensions, which amplifies use scope,
  • Key role in modern technologies – they find application in data components, brushless drives, diagnostic systems, and technologically advanced constructions.
  • Thanks to their power density, small magnets offer high operating force, with minimal size,

Cons

Characteristics of disadvantages of neodymium magnets: weaknesses and usage proposals
  • At strong impacts they can crack, therefore we advise placing them in strong housings. A metal housing provides additional protection against damage, as well as increases the magnet's durability.
  • Neodymium magnets decrease 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
  • Magnets exposed to a humid environment can corrode. Therefore when using outdoors, we recommend using water-impermeable magnets made of rubber, plastic or other material protecting against moisture
  • Limited possibility of making threads in the magnet and complex shapes - recommended is cover - magnetic holder.
  • Health risk resulting from small fragments of magnets can be dangerous, when accidentally swallowed, which is particularly important in the context of child health protection. It is also worth noting that small components of these devices can disrupt the diagnostic process medical in case of swallowing.
  • Due to complex production process, their price is higher than average,

Pull force analysis

Maximum lifting force for a neodymium magnet – what it depends on?

Information about lifting capacity was determined for the most favorable conditions, assuming:
  • with the contact of a sheet made of special test steel, ensuring full magnetic saturation
  • whose transverse dimension is min. 10 mm
  • with an polished contact surface
  • under conditions of ideal adhesion (metal-to-metal)
  • during pulling in a direction vertical to the plane
  • in stable room temperature

Magnet lifting force in use – key factors

Real force is influenced by working environment parameters, including (from most important):
  • Distance (between the magnet and the plate), because even a very small clearance (e.g. 0.5 mm) leads to a drastic drop in lifting capacity by up to 50% (this also applies to paint, corrosion or debris).
  • Loading method – declared lifting capacity refers to detachment vertically. When slipping, the magnet exhibits much less (often approx. 20-30% of maximum force).
  • Wall thickness – thin material does not allow full use of the magnet. Magnetic flux penetrates through instead of generating force.
  • Chemical composition of the base – mild steel gives the best results. Alloy steels decrease magnetic permeability and holding force.
  • Surface finish – ideal contact is possible only on smooth steel. Any scratches and bumps create air cushions, weakening the magnet.
  • Operating temperature – NdFeB sinters have a negative temperature coefficient. When it is hot they lose power, and in frost they can be stronger (up to a certain limit).

Lifting capacity was determined using a steel plate with a smooth surface of optimal thickness (min. 20 mm), under perpendicular detachment force, in contrast under parallel forces the holding force is lower. In addition, even a slight gap between the magnet and the plate decreases the lifting capacity.

H&S for magnets
Dust is flammable

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

Swallowing risk

NdFeB magnets are not toys. Eating multiple magnets can lead to them connecting inside the digestive tract, which constitutes a severe health hazard and requires urgent medical intervention.

Metal Allergy

Certain individuals suffer from a sensitization to nickel, which is the common plating for neodymium magnets. Extended handling may cause dermatitis. We strongly advise wear protective gloves.

Material brittleness

Neodymium magnets are sintered ceramics, which means they are very brittle. Collision of two magnets will cause them shattering into small pieces.

Threat to navigation

Be aware: rare earth magnets produce a field that disrupts precision electronics. Keep a separation from your mobile, tablet, and GPS.

ICD Warning

Health Alert: Neodymium magnets can deactivate heart devices and defibrillators. Do not approach if you have electronic implants.

Maximum temperature

Do not overheat. Neodymium magnets are sensitive to heat. If you need operation above 80°C, ask us about HT versions (H, SH, UH).

Finger safety

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

Handling rules

Before starting, check safety instructions. Uncontrolled attraction can destroy the magnet or hurt your hand. Be predictive.

Magnetic media

Very strong magnetic fields can erase data on payment cards, HDDs, and other magnetic media. Keep a distance of at least 10 cm.

Important! Need more info? Read our article: Are neodymium magnets dangerous?
Dhit sp. z o.o.

e-mail: bok@dhit.pl

tel: +48 888 99 98 98