MP 62x42x25 / N38 - ring magnet
ring magnet
Catalog no 030205
GTIN/EAN: 5906301812227
Diameter
62 mm [±0,1 mm]
internal diameter Ø
42 mm [±0,1 mm]
Height
25 mm [±0,1 mm]
Weight
306.31 g
Magnetization Direction
↑ axial
Load capacity
58.67 kg / 575.60 N
Magnetic Induction
389.14 mT / 3891 Gs
Coating
[NiCuNi] Nickel
165.00 ZŁ with VAT / pcs + price for transport
134.15 ZŁ net + 23% VAT / pcs
bulk discounts:
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Technical of the product - MP 62x42x25 / N38 - ring magnet
Specification / characteristics - MP 62x42x25 / N38 - ring magnet
| properties | values |
|---|---|
| Cat. no. | 030205 |
| GTIN/EAN | 5906301812227 |
| Production/Distribution | Dhit sp. z o.o. |
| Country of origin | Poland / China / Germany |
| Customs code | 85059029 |
| Diameter | 62 mm [±0,1 mm] |
| internal diameter Ø | 42 mm [±0,1 mm] |
| Height | 25 mm [±0,1 mm] |
| Weight | 306.31 g |
| Magnetization Direction | ↑ axial |
| Load capacity ~ ? | 58.67 kg / 575.60 N |
| Magnetic Induction ~ ? | 389.14 mT / 3891 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 |
Technical simulation of the assembly - report
The following data represent the result of a physical simulation. Values rely on models for the class Nd2Fe14B. Real-world parameters may differ from theoretical values. Use these calculations as a reference point during assembly planning.
Table 1: Static pull force (pull vs distance) - characteristics
MP 62x42x25 / N38
| Distance (mm) | Induction (Gauss) / mT | Pull Force (kg/lbs/g/N) | Risk Status |
|---|---|---|---|
| 0 mm |
4472 Gs
447.2 mT
|
58.67 kg / 129.35 pounds
58670.0 g / 575.6 N
|
crushing |
| 1 mm |
4338 Gs
433.8 mT
|
55.21 kg / 121.72 pounds
55213.2 g / 541.6 N
|
crushing |
| 2 mm |
4201 Gs
420.1 mT
|
51.77 kg / 114.13 pounds
51768.5 g / 507.8 N
|
crushing |
| 3 mm |
4061 Gs
406.1 mT
|
48.39 kg / 106.69 pounds
48394.9 g / 474.8 N
|
crushing |
| 5 mm |
3781 Gs
378.1 mT
|
41.94 kg / 92.47 pounds
41942.4 g / 411.5 N
|
crushing |
| 10 mm |
3097 Gs
309.7 mT
|
28.15 kg / 62.06 pounds
28148.0 g / 276.1 N
|
crushing |
| 15 mm |
2485 Gs
248.5 mT
|
18.12 kg / 39.94 pounds
18118.5 g / 177.7 N
|
crushing |
| 20 mm |
1972 Gs
197.2 mT
|
11.41 kg / 25.16 pounds
11412.7 g / 112.0 N
|
crushing |
| 30 mm |
1239 Gs
123.9 mT
|
4.51 kg / 9.93 pounds
4505.2 g / 44.2 N
|
medium risk |
| 50 mm |
533 Gs
53.3 mT
|
0.83 kg / 1.84 pounds
832.4 g / 8.2 N
|
weak grip |
Table 2: Slippage load (vertical surface)
MP 62x42x25 / N38
| Distance (mm) | Friction coefficient | Pull Force (kg/lbs/g/N) |
|---|---|---|
| 0 mm | Stal (~0.2) |
11.73 kg / 25.87 pounds
11734.0 g / 115.1 N
|
| 1 mm | Stal (~0.2) |
11.04 kg / 24.34 pounds
11042.0 g / 108.3 N
|
| 2 mm | Stal (~0.2) |
10.35 kg / 22.83 pounds
10354.0 g / 101.6 N
|
| 3 mm | Stal (~0.2) |
9.68 kg / 21.34 pounds
9678.0 g / 94.9 N
|
| 5 mm | Stal (~0.2) |
8.39 kg / 18.49 pounds
8388.0 g / 82.3 N
|
| 10 mm | Stal (~0.2) |
5.63 kg / 12.41 pounds
5630.0 g / 55.2 N
|
| 15 mm | Stal (~0.2) |
3.62 kg / 7.99 pounds
3624.0 g / 35.6 N
|
| 20 mm | Stal (~0.2) |
2.28 kg / 5.03 pounds
2282.0 g / 22.4 N
|
| 30 mm | Stal (~0.2) |
0.90 kg / 1.99 pounds
902.0 g / 8.8 N
|
| 50 mm | Stal (~0.2) |
0.17 kg / 0.37 pounds
166.0 g / 1.6 N
|
Table 3: Wall mounting (shearing) - vertical pull
MP 62x42x25 / N38
| Surface type | Friction coefficient / % Mocy | Max load (kg/lbs/g/N) |
|---|---|---|
| Raw steel |
µ = 0.3
30% Nominalnej Siły
|
17.60 kg / 38.80 pounds
17601.0 g / 172.7 N
|
| Painted steel (standard) |
µ = 0.2
20% Nominalnej Siły
|
11.73 kg / 25.87 pounds
11734.0 g / 115.1 N
|
| Oily/slippery steel |
µ = 0.1
10% Nominalnej Siły
|
5.87 kg / 12.93 pounds
5867.0 g / 57.6 N
|
| Magnet with anti-slip rubber |
µ = 0.5
50% Nominalnej Siły
|
29.34 kg / 64.67 pounds
29335.0 g / 287.8 N
|
Table 4: Material efficiency (substrate influence) - power losses
MP 62x42x25 / N38
| Steel thickness (mm) | % power | Real pull force (kg/lbs/g/N) |
|---|---|---|
| 0.5 mm |
|
1.96 kg / 4.31 pounds
1955.7 g / 19.2 N
|
| 1 mm |
|
4.89 kg / 10.78 pounds
4889.2 g / 48.0 N
|
| 2 mm |
|
9.78 kg / 21.56 pounds
9778.3 g / 95.9 N
|
| 3 mm |
|
14.67 kg / 32.34 pounds
14667.5 g / 143.9 N
|
| 5 mm |
|
24.45 kg / 53.89 pounds
24445.8 g / 239.8 N
|
| 10 mm |
|
48.89 kg / 107.79 pounds
48891.7 g / 479.6 N
|
| 11 mm |
|
53.78 kg / 118.57 pounds
53780.8 g / 527.6 N
|
| 12 mm |
|
58.67 kg / 129.35 pounds
58670.0 g / 575.6 N
|
Table 5: Thermal resistance (stability) - power drop
MP 62x42x25 / N38
| Ambient temp. (°C) | Power loss | Remaining pull (kg/lbs/g/N) | Status |
|---|---|---|---|
| 20 °C | 0.0% |
58.67 kg / 129.35 pounds
58670.0 g / 575.6 N
|
OK |
| 40 °C | -2.2% |
57.38 kg / 126.50 pounds
57379.3 g / 562.9 N
|
OK |
| 60 °C | -4.4% |
56.09 kg / 123.65 pounds
56088.5 g / 550.2 N
|
OK |
| 80 °C | -6.6% |
54.80 kg / 120.81 pounds
54797.8 g / 537.6 N
|
|
| 100 °C | -28.8% |
41.77 kg / 92.09 pounds
41773.0 g / 409.8 N
|
Table 6: Magnet-Magnet interaction (attraction) - field collision
MP 62x42x25 / N38
| Gap (mm) | Attraction (kg/lbs) (N-S) | Shear Force (kg/lbs/g/N) | Repulsion (kg/lbs) (N-N) |
|---|---|---|---|
| 0 mm |
264.93 kg / 584.07 pounds
5 588 Gs
|
39.74 kg / 87.61 pounds
39740 g / 389.8 N
|
N/A |
| 1 mm |
257.19 kg / 567.00 pounds
8 812 Gs
|
38.58 kg / 85.05 pounds
38578 g / 378.4 N
|
231.47 kg / 510.30 pounds
~0 Gs
|
| 2 mm |
249.32 kg / 549.66 pounds
8 676 Gs
|
37.40 kg / 82.45 pounds
37398 g / 366.9 N
|
224.39 kg / 494.69 pounds
~0 Gs
|
| 3 mm |
241.51 kg / 532.44 pounds
8 539 Gs
|
36.23 kg / 79.87 pounds
36227 g / 355.4 N
|
217.36 kg / 479.19 pounds
~0 Gs
|
| 5 mm |
226.10 kg / 498.47 pounds
8 262 Gs
|
33.92 kg / 74.77 pounds
33915 g / 332.7 N
|
203.49 kg / 448.62 pounds
~0 Gs
|
| 10 mm |
189.40 kg / 417.55 pounds
7 562 Gs
|
28.41 kg / 62.63 pounds
28409 g / 278.7 N
|
170.46 kg / 375.79 pounds
~0 Gs
|
| 20 mm |
127.11 kg / 280.22 pounds
6 195 Gs
|
19.07 kg / 42.03 pounds
19066 g / 187.0 N
|
114.40 kg / 252.20 pounds
~0 Gs
|
| 50 mm |
32.28 kg / 71.17 pounds
3 122 Gs
|
4.84 kg / 10.68 pounds
4843 g / 47.5 N
|
29.06 kg / 64.06 pounds
~0 Gs
|
| 60 mm |
20.34 kg / 44.85 pounds
2 478 Gs
|
3.05 kg / 6.73 pounds
3052 g / 29.9 N
|
18.31 kg / 40.36 pounds
~0 Gs
|
| 70 mm |
12.99 kg / 28.63 pounds
1 980 Gs
|
1.95 kg / 4.29 pounds
1948 g / 19.1 N
|
11.69 kg / 25.77 pounds
~0 Gs
|
| 80 mm |
8.43 kg / 18.59 pounds
1 595 Gs
|
1.26 kg / 2.79 pounds
1265 g / 12.4 N
|
7.59 kg / 16.73 pounds
~0 Gs
|
| 90 mm |
5.58 kg / 12.29 pounds
1 298 Gs
|
0.84 kg / 1.84 pounds
836 g / 8.2 N
|
5.02 kg / 11.06 pounds
~0 Gs
|
| 100 mm |
3.76 kg / 8.29 pounds
1 065 Gs
|
0.56 kg / 1.24 pounds
564 g / 5.5 N
|
3.38 kg / 7.46 pounds
~0 Gs
|
Table 7: Protective zones (implants) - precautionary measures
MP 62x42x25 / N38
| Object / Device | Limit (Gauss) / mT | Safe distance |
|---|---|---|
| Pacemaker | 5 Gs (0.5 mT) | 32.5 cm |
| Hearing aid | 10 Gs (1.0 mT) | 25.5 cm |
| Mechanical watch | 20 Gs (2.0 mT) | 20.0 cm |
| Mobile device | 40 Gs (4.0 mT) | 15.5 cm |
| Remote | 50 Gs (5.0 mT) | 14.0 cm |
| Payment card | 400 Gs (40.0 mT) | 6.0 cm |
| HDD hard drive | 600 Gs (60.0 mT) | 5.0 cm |
Table 8: Collisions (kinetic energy) - warning
MP 62x42x25 / N38
| Start from (mm) | Speed (km/h) | Energy (J) | Predicted outcome |
|---|---|---|---|
| 10 mm |
17.65 km/h
(4.90 m/s)
|
3.68 J | |
| 30 mm |
25.31 km/h
(7.03 m/s)
|
7.57 J | |
| 50 mm |
31.49 km/h
(8.75 m/s)
|
11.72 J | |
| 100 mm |
44.16 km/h
(12.27 m/s)
|
23.04 J |
Table 9: Coating parameters (durability)
MP 62x42x25 / 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 62x42x25 / N38
| Parameter | Value | SI Unit / Description |
|---|---|---|
| Magnetic Flux | 100 906 Mx | 1009.1 µWb |
| Pc Coefficient | 0.64 | High (Stable) |
Table 11: Physics of underwater searching
MP 62x42x25 / N38
| Environment | Effective steel pull | Effect |
|---|---|---|
| Air (land) | 58.67 kg | Standard |
| Water (riverbed) |
67.18 kg
(+8.51 kg buoyancy gain)
|
+14.5% |
1. Wall mount (shear)
*Warning: On a vertical surface, the magnet holds merely ~20% of its max power.
2. Steel thickness impact
*Thin metal sheet (e.g. computer case) severely limits the holding force.
3. Temperature resistance
*For N38 grade, the critical limit is 80°C.
4. Demagnetization curve and operating point (B-H)
chart generated for the permeance coefficient Pc (Permeance Coefficient) = 0.64
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.
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 |
Other deals
Pros and cons of rare earth magnets.
Pros
- They have stable power, and over around 10 years their performance decreases symbolically – ~1% (according to theory),
- They show high resistance to demagnetization induced by external field influence,
- Thanks to the shimmering finish, the layer of Ni-Cu-Ni, gold, or silver gives an elegant appearance,
- Magnets exhibit huge magnetic induction on the outer side,
- 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...
- Possibility of accurate machining as well as adapting to complex conditions,
- Wide application in future technologies – they are utilized in data components, electric motors, medical equipment, as well as multitasking production systems.
- Compactness – despite small sizes they provide effective action, making them ideal for precision applications
Cons
- They are prone to damage upon too strong impacts. To avoid cracks, it is worth securing magnets in special housings. Such protection not only shields the magnet but also increases its resistance to damage
- 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 stability even at temperatures up to 230°C
- When exposed to humidity, magnets usually rust. For applications outside, it is recommended to use protective magnets, such as magnets in rubber or plastics, which prevent oxidation as well as corrosion.
- We recommend casing - magnetic mount, due to difficulties in producing threads inside the magnet and complex shapes.
- Possible danger related to microscopic parts of magnets can be dangerous, in case of ingestion, which is particularly important in the context of child safety. Furthermore, small components of these magnets can be problematic in diagnostics medical in case of swallowing.
- Due to neodymium price, their price exceeds standard values,
Holding force characteristics
Detachment force of the magnet in optimal conditions – what it depends on?
- on a base made of structural steel, effectively closing the magnetic flux
- with a thickness of at least 10 mm
- with a plane perfectly flat
- with direct contact (no coatings)
- for force applied at a right angle (in the magnet axis)
- in neutral thermal conditions
Determinants of lifting force in real conditions
- Air gap (betwixt the magnet and the plate), since even a microscopic distance (e.g. 0.5 mm) can cause a reduction in force by up to 50% (this also applies to varnish, corrosion or dirt).
- Direction of force – maximum parameter is available only during perpendicular pulling. The shear force of the magnet along the surface is usually several times smaller (approx. 1/5 of the lifting capacity).
- Substrate thickness – to utilize 100% power, the steel must be sufficiently thick. Paper-thin metal restricts the attraction force (the magnet "punches through" it).
- Material composition – not every steel reacts the same. Alloy additives worsen the interaction with the magnet.
- Surface quality – the smoother and more polished the plate, the better the adhesion and stronger the hold. Roughness creates an air distance.
- Operating temperature – NdFeB sinters have a sensitivity to temperature. When it is hot they are weaker, and in frost they can be stronger (up to a certain limit).
Lifting capacity was assessed with the use of a polished steel plate of optimal thickness (min. 20 mm), under perpendicular pulling force, in contrast under attempts to slide the magnet the holding force is lower. Additionally, even a slight gap between the magnet’s surface and the plate decreases the load capacity.
Safe handling of NdFeB magnets
Nickel coating and allergies
Warning for allergy sufferers: The nickel-copper-nickel coating consists of nickel. If an allergic reaction appears, immediately stop handling magnets and wear gloves.
Product not for children
Only for adults. Small elements pose a choking risk, causing serious injuries. Keep out of reach of children and animals.
GPS Danger
A strong magnetic field interferes with the operation of compasses in phones and navigation systems. Maintain magnets near a device to avoid damaging the sensors.
Protective goggles
Despite metallic appearance, the material is brittle and cannot withstand shocks. Avoid impacts, as the magnet may shatter into hazardous fragments.
Caution required
Before starting, check safety instructions. Uncontrolled attraction can destroy the magnet or injure your hand. Think ahead.
Health Danger
Warning for patients: Powerful magnets affect electronics. Keep minimum 30 cm distance or ask another person to handle the magnets.
Mechanical processing
Fire hazard: Neodymium dust is explosive. Do not process magnets without safety gear as this risks ignition.
Pinching danger
Danger of trauma: The attraction force is so immense that it can result in blood blisters, crushing, and even bone fractures. Protective gloves are recommended.
Safe distance
Intense magnetic fields can erase data on credit cards, HDDs, and other magnetic media. Keep a distance of min. 10 cm.
Heat warning
Keep cool. Neodymium magnets are sensitive to temperature. If you require operation above 80°C, look for HT versions (H, SH, UH).
