MP 20x10x5 / N38 - ring magnet
ring magnet
Catalog no 030184
GTIN/EAN: 5906301812012
Diameter
20 mm [±0,1 mm]
internal diameter Ø
10 mm [±0,1 mm]
Height
5 mm [±0,1 mm]
Weight
8.84 g
Magnetization Direction
↑ axial
Load capacity
5.20 kg / 50.97 N
Magnetic Induction
277.16 mT / 2772 Gs
Coating
[NiCuNi] Nickel
4.50 ZŁ with VAT / pcs + price for transport
3.66 ZŁ net + 23% VAT / pcs
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Physical properties - MP 20x10x5 / N38 - ring magnet
Specification / characteristics - MP 20x10x5 / N38 - ring magnet
| properties | values |
|---|---|
| Cat. no. | 030184 |
| GTIN/EAN | 5906301812012 |
| Production/Distribution | Dhit sp. z o.o. |
| Country of origin | Poland / China / Germany |
| Customs code | 85059029 |
| Diameter | 20 mm [±0,1 mm] |
| internal diameter Ø | 10 mm [±0,1 mm] |
| Height | 5 mm [±0,1 mm] |
| Weight | 8.84 g |
| Magnetization Direction | ↑ axial |
| Load capacity ~ ? | 5.20 kg / 50.97 N |
| Magnetic Induction ~ ? | 277.16 mT / 2772 Gs |
| Coating | [NiCuNi] Nickel |
| Manufacturing Tolerance | ±0.1 mm |
Magnetic properties of material N38
| 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 - data
Presented data represent the outcome of a physical analysis. Values rely on models for the class Nd2Fe14B. Real-world parameters might slightly differ from theoretical values. Treat these data as a preliminary roadmap when designing systems.
Table 1: Static pull force (pull vs distance) - power drop
MP 20x10x5 / N38
| Distance (mm) | Induction (Gauss) / mT | Pull Force (kg/lbs/g/N) | Risk Status |
|---|---|---|---|
| 0 mm |
5917 Gs
591.7 mT
|
5.20 kg / 11.46 pounds
5200.0 g / 51.0 N
|
medium risk |
| 1 mm |
5321 Gs
532.1 mT
|
4.21 kg / 9.27 pounds
4205.9 g / 41.3 N
|
medium risk |
| 2 mm |
4736 Gs
473.6 mT
|
3.33 kg / 7.35 pounds
3332.2 g / 32.7 N
|
medium risk |
| 3 mm |
4184 Gs
418.4 mT
|
2.60 kg / 5.73 pounds
2600.0 g / 25.5 N
|
medium risk |
| 5 mm |
3216 Gs
321.6 mT
|
1.54 kg / 3.39 pounds
1536.2 g / 15.1 N
|
safe |
| 10 mm |
1650 Gs
165.0 mT
|
0.40 kg / 0.89 pounds
404.2 g / 4.0 N
|
safe |
| 15 mm |
907 Gs
90.7 mT
|
0.12 kg / 0.27 pounds
122.3 g / 1.2 N
|
safe |
| 20 mm |
544 Gs
54.4 mT
|
0.04 kg / 0.10 pounds
44.0 g / 0.4 N
|
safe |
| 30 mm |
240 Gs
24.0 mT
|
0.01 kg / 0.02 pounds
8.5 g / 0.1 N
|
safe |
| 50 mm |
75 Gs
7.5 mT
|
0.00 kg / 0.00 pounds
0.8 g / 0.0 N
|
safe |
Table 2: Shear force (vertical surface)
MP 20x10x5 / N38
| Distance (mm) | Friction coefficient | Pull Force (kg/lbs/g/N) |
|---|---|---|
| 0 mm | Stal (~0.2) |
1.04 kg / 2.29 pounds
1040.0 g / 10.2 N
|
| 1 mm | Stal (~0.2) |
0.84 kg / 1.86 pounds
842.0 g / 8.3 N
|
| 2 mm | Stal (~0.2) |
0.67 kg / 1.47 pounds
666.0 g / 6.5 N
|
| 3 mm | Stal (~0.2) |
0.52 kg / 1.15 pounds
520.0 g / 5.1 N
|
| 5 mm | Stal (~0.2) |
0.31 kg / 0.68 pounds
308.0 g / 3.0 N
|
| 10 mm | Stal (~0.2) |
0.08 kg / 0.18 pounds
80.0 g / 0.8 N
|
| 15 mm | Stal (~0.2) |
0.02 kg / 0.05 pounds
24.0 g / 0.2 N
|
| 20 mm | Stal (~0.2) |
0.01 kg / 0.02 pounds
8.0 g / 0.1 N
|
| 30 mm | Stal (~0.2) |
0.00 kg / 0.00 pounds
2.0 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 (shearing) - behavior on slippery surfaces
MP 20x10x5 / N38
| Surface type | Friction coefficient / % Mocy | Max load (kg/lbs/g/N) |
|---|---|---|
| Raw steel |
µ = 0.3
30% Nominalnej Siły
|
1.56 kg / 3.44 pounds
1560.0 g / 15.3 N
|
| Painted steel (standard) |
µ = 0.2
20% Nominalnej Siły
|
1.04 kg / 2.29 pounds
1040.0 g / 10.2 N
|
| Oily/slippery steel |
µ = 0.1
10% Nominalnej Siły
|
0.52 kg / 1.15 pounds
520.0 g / 5.1 N
|
| Magnet with anti-slip rubber |
µ = 0.5
50% Nominalnej Siły
|
2.60 kg / 5.73 pounds
2600.0 g / 25.5 N
|
Table 4: Material efficiency (substrate influence) - sheet metal selection
MP 20x10x5 / N38
| Steel thickness (mm) | % power | Real pull force (kg/lbs/g/N) |
|---|---|---|
| 0.5 mm |
|
0.52 kg / 1.15 pounds
520.0 g / 5.1 N
|
| 1 mm |
|
1.30 kg / 2.87 pounds
1300.0 g / 12.8 N
|
| 2 mm |
|
2.60 kg / 5.73 pounds
2600.0 g / 25.5 N
|
| 3 mm |
|
3.90 kg / 8.60 pounds
3900.0 g / 38.3 N
|
| 5 mm |
|
5.20 kg / 11.46 pounds
5200.0 g / 51.0 N
|
| 10 mm |
|
5.20 kg / 11.46 pounds
5200.0 g / 51.0 N
|
| 11 mm |
|
5.20 kg / 11.46 pounds
5200.0 g / 51.0 N
|
| 12 mm |
|
5.20 kg / 11.46 pounds
5200.0 g / 51.0 N
|
Table 5: Working in heat (stability) - resistance threshold
MP 20x10x5 / N38
| Ambient temp. (°C) | Power loss | Remaining pull (kg/lbs/g/N) | Status |
|---|---|---|---|
| 20 °C | 0.0% |
5.20 kg / 11.46 pounds
5200.0 g / 51.0 N
|
OK |
| 40 °C | -2.2% |
5.09 kg / 11.21 pounds
5085.6 g / 49.9 N
|
OK |
| 60 °C | -4.4% |
4.97 kg / 10.96 pounds
4971.2 g / 48.8 N
|
OK |
| 80 °C | -6.6% |
4.86 kg / 10.71 pounds
4856.8 g / 47.6 N
|
|
| 100 °C | -28.8% |
3.70 kg / 8.16 pounds
3702.4 g / 36.3 N
|
Table 6: Magnet-Magnet interaction (attraction) - field range
MP 20x10x5 / N38
| Gap (mm) | Attraction (kg/lbs) (N-S) | Sliding Force (kg/lbs/g/N) | Repulsion (kg/lbs) (N-N) |
|---|---|---|---|
| 0 mm |
54.03 kg / 119.11 pounds
6 121 Gs
|
8.10 kg / 17.87 pounds
8104 g / 79.5 N
|
N/A |
| 1 mm |
48.76 kg / 107.50 pounds
11 242 Gs
|
7.31 kg / 16.13 pounds
7314 g / 71.8 N
|
43.89 kg / 96.75 pounds
~0 Gs
|
| 2 mm |
43.70 kg / 96.34 pounds
10 642 Gs
|
6.55 kg / 14.45 pounds
6555 g / 64.3 N
|
39.33 kg / 86.71 pounds
~0 Gs
|
| 3 mm |
38.98 kg / 85.94 pounds
10 051 Gs
|
5.85 kg / 12.89 pounds
5847 g / 57.4 N
|
35.08 kg / 77.34 pounds
~0 Gs
|
| 5 mm |
30.63 kg / 67.54 pounds
8 910 Gs
|
4.60 kg / 10.13 pounds
4595 g / 45.1 N
|
27.57 kg / 60.78 pounds
~0 Gs
|
| 10 mm |
15.96 kg / 35.19 pounds
6 432 Gs
|
2.39 kg / 5.28 pounds
2394 g / 23.5 N
|
14.36 kg / 31.67 pounds
~0 Gs
|
| 20 mm |
4.20 kg / 9.26 pounds
3 299 Gs
|
0.63 kg / 1.39 pounds
630 g / 6.2 N
|
3.78 kg / 8.33 pounds
~0 Gs
|
| 50 mm |
0.19 kg / 0.42 pounds
702 Gs
|
0.03 kg / 0.06 pounds
29 g / 0.3 N
|
0.17 kg / 0.38 pounds
~0 Gs
|
| 60 mm |
0.09 kg / 0.20 pounds
480 Gs
|
0.01 kg / 0.03 pounds
13 g / 0.1 N
|
0.08 kg / 0.18 pounds
~0 Gs
|
| 70 mm |
0.05 kg / 0.10 pounds
342 Gs
|
0.01 kg / 0.01 pounds
7 g / 0.1 N
|
0.04 kg / 0.09 pounds
~0 Gs
|
| 80 mm |
0.02 kg / 0.05 pounds
253 Gs
|
0.00 kg / 0.01 pounds
4 g / 0.0 N
|
0.02 kg / 0.05 pounds
~0 Gs
|
| 90 mm |
0.01 kg / 0.03 pounds
193 Gs
|
0.00 kg / 0.00 pounds
2 g / 0.0 N
|
0.01 kg / 0.03 pounds
~0 Gs
|
| 100 mm |
0.01 kg / 0.02 pounds
150 Gs
|
0.00 kg / 0.00 pounds
1 g / 0.0 N
|
0.00 kg / 0.00 pounds
~0 Gs
|
Table 7: Safety (HSE) (implants) - precautionary measures
MP 20x10x5 / N38
| Object / Device | Limit (Gauss) / mT | Safe distance |
|---|---|---|
| Pacemaker | 5 Gs (0.5 mT) | 14.5 cm |
| Hearing aid | 10 Gs (1.0 mT) | 11.5 cm |
| Timepiece | 20 Gs (2.0 mT) | 9.0 cm |
| Mobile device | 40 Gs (4.0 mT) | 6.5 cm |
| Remote | 50 Gs (5.0 mT) | 6.0 cm |
| Payment card | 400 Gs (40.0 mT) | 2.5 cm |
| HDD hard drive | 600 Gs (60.0 mT) | 2.0 cm |
Table 8: Impact energy (kinetic energy) - warning
MP 20x10x5 / N38
| Start from (mm) | Speed (km/h) | Energy (J) | Predicted outcome |
|---|---|---|---|
| 10 mm |
25.62 km/h
(7.12 m/s)
|
0.22 J | |
| 30 mm |
42.41 km/h
(11.78 m/s)
|
0.61 J | |
| 50 mm |
54.70 km/h
(15.19 m/s)
|
1.02 J | |
| 100 mm |
77.35 km/h
(21.49 m/s)
|
2.04 J |
Table 9: Surface protection spec
MP 20x10x5 / 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)
MP 20x10x5 / N38
| Parameter | Value | SI Unit / Description |
|---|---|---|
| Magnetic Flux | 16 116 Mx | 161.2 µWb |
| Pc Coefficient | 1.13 | High (Stable) |
Table 11: Hydrostatics and buoyancy
MP 20x10x5 / N38
| Environment | Effective steel pull | Effect |
|---|---|---|
| Air (land) | 5.20 kg | Standard |
| Water (riverbed) |
5.95 kg
(+0.75 kg buoyancy gain)
|
+14.5% |
1. Shear force
*Warning: On a vertical wall, the magnet holds only a fraction of its max power.
2. Plate thickness effect
*Thin steel (e.g. 0.5mm PC case) drastically reduces the holding force.
3. Heat tolerance
*For N38 material, the critical limit is 80°C.
4. Demagnetization curve and operating point (B-H)
chart generated for the permeance coefficient Pc (Permeance Coefficient) = 1.13
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.
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 |
Other offers
Strengths and weaknesses of rare earth magnets.
Advantages
- They have stable power, and over around ten years their performance decreases symbolically – ~1% (according to theory),
- They feature excellent resistance to magnetic field loss as a result of external magnetic sources,
- In other words, due to the glossy finish of gold, the element gains visual value,
- The surface of neodymium magnets generates a unique magnetic field – this is a distinguishing feature,
- Thanks to resistance to high temperature, they are able to function (depending on the shape) even at temperatures up to 230°C and higher...
- Thanks to freedom in constructing and the capacity to adapt to specific needs,
- Wide application in modern technologies – they are utilized in mass storage devices, motor assemblies, medical equipment, also multitasking production systems.
- Compactness – despite small sizes they offer powerful magnetic field, making them ideal for precision applications
Disadvantages
- To avoid cracks upon strong impacts, we suggest using special steel holders. Such a solution protects the magnet and simultaneously improves its durability.
- We warn that neodymium magnets can lose their strength at high temperatures. To prevent this, we recommend our specialized [AH] magnets, which work effectively even at 230°C.
- Magnets exposed to a humid environment can corrode. Therefore when using outdoors, we suggest using water-impermeable magnets made of rubber, plastic or other material protecting against moisture
- Limited ability of creating nuts in the magnet and complex forms - preferred is cover - magnet mounting.
- Health risk to health – tiny shards of magnets can be dangerous, when accidentally swallowed, which gains importance in the context of child health protection. It is also worth noting that tiny parts of these magnets can disrupt the diagnostic process medical after entering the body.
- Due to neodymium price, their price is relatively high,
Lifting parameters
Maximum magnetic pulling force – what contributes to it?
- with the use of a sheet made of low-carbon steel, guaranteeing full magnetic saturation
- whose transverse dimension equals approx. 10 mm
- with an polished contact surface
- under conditions of ideal adhesion (surface-to-surface)
- for force acting at a right angle (in the magnet axis)
- at room temperature
Key elements affecting lifting force
- Space between surfaces – every millimeter of separation (caused e.g. by veneer or unevenness) significantly weakens the magnet efficiency, often by half at just 0.5 mm.
- Pull-off angle – remember that the magnet has greatest strength perpendicularly. Under sliding down, the capacity drops significantly, often to levels of 20-30% of the nominal value.
- Steel thickness – insufficiently thick steel does not close the flux, causing part of the flux to be escaped to the other side.
- Material type – the best choice is high-permeability steel. Stainless steels may have worse magnetic properties.
- Smoothness – full contact is obtained only on smooth steel. Rough texture reduce the real contact area, weakening the magnet.
- Thermal environment – heating the magnet results in weakening of force. It is worth remembering the thermal limit for a given model.
Lifting capacity was assessed by applying a smooth steel plate of optimal thickness (min. 20 mm), under perpendicular detachment force, whereas under shearing force the lifting capacity is smaller. Additionally, even a slight gap between the magnet and the plate reduces the load capacity.
Warnings
Fragile material
Neodymium magnets are sintered ceramics, meaning they are prone to chipping. Impact of two magnets leads to them breaking into shards.
Heat warning
Standard neodymium magnets (grade N) undergo demagnetization when the temperature surpasses 80°C. The loss of strength is permanent.
ICD Warning
People with a pacemaker must keep an large gap from magnets. The magnetic field can stop the functioning of the life-saving device.
Allergic reactions
Nickel alert: The Ni-Cu-Ni coating contains nickel. If an allergic reaction happens, cease handling magnets and wear gloves.
Fire warning
Fire warning: Neodymium dust is highly flammable. Avoid machining magnets without safety gear as this may cause fire.
Pinching danger
Protect your hands. Two large magnets will join immediately with a force of several hundred kilograms, destroying anything in their path. Exercise extreme caution!
GPS and phone interference
An intense magnetic field disrupts the operation of compasses in smartphones and navigation systems. Do not bring magnets close to a smartphone to avoid damaging the sensors.
Keep away from computers
Data protection: Strong magnets can damage data carriers and delicate electronics (pacemakers, hearing aids, timepieces).
This is not a toy
Product intended for adults. Tiny parts can be swallowed, leading to intestinal necrosis. Store away from children and animals.
Handling rules
Before use, check safety instructions. Uncontrolled attraction can destroy the magnet or hurt your hand. Think ahead.
