MPL 40x20x4x2[7/3.5] / N38 - lamellar magnet
lamellar magnet
Catalog no 020159
GTIN/EAN: 5906301811657
length
40 mm [±0,1 mm]
Width
20 mm [±0,1 mm]
Height
4 mm [±0,1 mm]
Weight
24 g
Magnetization Direction
↑ axial
Load capacity
7.52 kg / 73.80 N
Magnetic Induction
168.28 mT / 1683 Gs
Coating
[NiCuNi] Nickel
17.96 ZŁ with VAT / pcs + price for transport
14.60 ZŁ net + 23% VAT / pcs
bulk discounts:
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Technical data of the product - MPL 40x20x4x2[7/3.5] / N38 - lamellar magnet
Specification / characteristics - MPL 40x20x4x2[7/3.5] / N38 - lamellar magnet
| properties | values |
|---|---|
| Cat. no. | 020159 |
| GTIN/EAN | 5906301811657 |
| Production/Distribution | Dhit sp. z o.o. |
| Country of origin | Poland / China / Germany |
| Customs code | 85059029 |
| length | 40 mm [±0,1 mm] |
| Width | 20 mm [±0,1 mm] |
| Height | 4 mm [±0,1 mm] |
| Weight | 24 g |
| Magnetization Direction | ↑ axial |
| Load capacity ~ ? | 7.52 kg / 73.80 N |
| Magnetic Induction ~ ? | 168.28 mT / 1683 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 |
Engineering analysis of the product - data
The following data represent the result of a physical calculation. Results rely on models for the class Nd2Fe14B. Actual conditions may deviate from the simulation results. Please consider these calculations as a supplementary guide during assembly planning.
Table 1: Static pull force (pull vs gap) - interaction chart
MPL 40x20x4x2[7/3.5] / N38
| Distance (mm) | Induction (Gauss) / mT | Pull Force (kg/lbs/g/N) | Risk Status |
|---|---|---|---|
| 0 mm |
1683 Gs
168.3 mT
|
7.52 kg / 16.58 LBS
7520.0 g / 73.8 N
|
warning |
| 1 mm |
1613 Gs
161.3 mT
|
6.91 kg / 15.24 LBS
6913.8 g / 67.8 N
|
warning |
| 2 mm |
1524 Gs
152.4 mT
|
6.17 kg / 13.61 LBS
6172.9 g / 60.6 N
|
warning |
| 3 mm |
1423 Gs
142.3 mT
|
5.38 kg / 11.86 LBS
5379.4 g / 52.8 N
|
warning |
| 5 mm |
1207 Gs
120.7 mT
|
3.87 kg / 8.53 LBS
3869.8 g / 38.0 N
|
warning |
| 10 mm |
744 Gs
74.4 mT
|
1.47 kg / 3.24 LBS
1469.3 g / 14.4 N
|
weak grip |
| 15 mm |
455 Gs
45.5 mT
|
0.55 kg / 1.21 LBS
550.7 g / 5.4 N
|
weak grip |
| 20 mm |
288 Gs
28.8 mT
|
0.22 kg / 0.49 LBS
220.3 g / 2.2 N
|
weak grip |
| 30 mm |
129 Gs
12.9 mT
|
0.04 kg / 0.10 LBS
44.4 g / 0.4 N
|
weak grip |
| 50 mm |
38 Gs
3.8 mT
|
0.00 kg / 0.01 LBS
3.8 g / 0.0 N
|
weak grip |
Table 2: Vertical capacity (wall)
MPL 40x20x4x2[7/3.5] / N38
| Distance (mm) | Friction coefficient | Pull Force (kg/lbs/g/N) |
|---|---|---|
| 0 mm | Stal (~0.2) |
1.50 kg / 3.32 LBS
1504.0 g / 14.8 N
|
| 1 mm | Stal (~0.2) |
1.38 kg / 3.05 LBS
1382.0 g / 13.6 N
|
| 2 mm | Stal (~0.2) |
1.23 kg / 2.72 LBS
1234.0 g / 12.1 N
|
| 3 mm | Stal (~0.2) |
1.08 kg / 2.37 LBS
1076.0 g / 10.6 N
|
| 5 mm | Stal (~0.2) |
0.77 kg / 1.71 LBS
774.0 g / 7.6 N
|
| 10 mm | Stal (~0.2) |
0.29 kg / 0.65 LBS
294.0 g / 2.9 N
|
| 15 mm | Stal (~0.2) |
0.11 kg / 0.24 LBS
110.0 g / 1.1 N
|
| 20 mm | Stal (~0.2) |
0.04 kg / 0.10 LBS
44.0 g / 0.4 N
|
| 30 mm | Stal (~0.2) |
0.01 kg / 0.02 LBS
8.0 g / 0.1 N
|
| 50 mm | Stal (~0.2) |
0.00 kg / 0.00 LBS
0.0 g / 0.0 N
|
Table 3: Vertical assembly (sliding) - behavior on slippery surfaces
MPL 40x20x4x2[7/3.5] / N38
| Surface type | Friction coefficient / % Mocy | Max load (kg/lbs/g/N) |
|---|---|---|
| Raw steel |
µ = 0.3
30% Nominalnej Siły
|
2.26 kg / 4.97 LBS
2256.0 g / 22.1 N
|
| Painted steel (standard) |
µ = 0.2
20% Nominalnej Siły
|
1.50 kg / 3.32 LBS
1504.0 g / 14.8 N
|
| Oily/slippery steel |
µ = 0.1
10% Nominalnej Siły
|
0.75 kg / 1.66 LBS
752.0 g / 7.4 N
|
| Magnet with anti-slip rubber |
µ = 0.5
50% Nominalnej Siły
|
3.76 kg / 8.29 LBS
3760.0 g / 36.9 N
|
Table 4: Steel thickness (substrate influence) - power losses
MPL 40x20x4x2[7/3.5] / N38
| Steel thickness (mm) | % power | Real pull force (kg/lbs/g/N) |
|---|---|---|
| 0.5 mm |
|
0.75 kg / 1.66 LBS
752.0 g / 7.4 N
|
| 1 mm |
|
1.88 kg / 4.14 LBS
1880.0 g / 18.4 N
|
| 2 mm |
|
3.76 kg / 8.29 LBS
3760.0 g / 36.9 N
|
| 3 mm |
|
5.64 kg / 12.43 LBS
5640.0 g / 55.3 N
|
| 5 mm |
|
7.52 kg / 16.58 LBS
7520.0 g / 73.8 N
|
| 10 mm |
|
7.52 kg / 16.58 LBS
7520.0 g / 73.8 N
|
| 11 mm |
|
7.52 kg / 16.58 LBS
7520.0 g / 73.8 N
|
| 12 mm |
|
7.52 kg / 16.58 LBS
7520.0 g / 73.8 N
|
Table 5: Working in heat (material behavior) - thermal limit
MPL 40x20x4x2[7/3.5] / N38
| Ambient temp. (°C) | Power loss | Remaining pull (kg/lbs/g/N) | Status |
|---|---|---|---|
| 20 °C | 0.0% |
7.52 kg / 16.58 LBS
7520.0 g / 73.8 N
|
OK |
| 40 °C | -2.2% |
7.35 kg / 16.21 LBS
7354.6 g / 72.1 N
|
OK |
| 60 °C | -4.4% |
7.19 kg / 15.85 LBS
7189.1 g / 70.5 N
|
|
| 80 °C | -6.6% |
7.02 kg / 15.48 LBS
7023.7 g / 68.9 N
|
|
| 100 °C | -28.8% |
5.35 kg / 11.80 LBS
5354.2 g / 52.5 N
|
Table 6: Magnet-Magnet interaction (repulsion) - forces in the system
MPL 40x20x4x2[7/3.5] / N38
| Gap (mm) | Attraction (kg/lbs) (N-S) | Shear Force (kg/lbs/g/N) | Repulsion (kg/lbs) (N-N) |
|---|---|---|---|
| 0 mm |
13.96 kg / 30.78 LBS
2 997 Gs
|
2.09 kg / 4.62 LBS
2094 g / 20.5 N
|
N/A |
| 1 mm |
13.44 kg / 29.64 LBS
3 302 Gs
|
2.02 kg / 4.45 LBS
2017 g / 19.8 N
|
12.10 kg / 26.68 LBS
~0 Gs
|
| 2 mm |
12.84 kg / 28.30 LBS
3 227 Gs
|
1.93 kg / 4.25 LBS
1926 g / 18.9 N
|
11.55 kg / 25.47 LBS
~0 Gs
|
| 3 mm |
12.17 kg / 26.83 LBS
3 142 Gs
|
1.83 kg / 4.02 LBS
1826 g / 17.9 N
|
10.95 kg / 24.15 LBS
~0 Gs
|
| 5 mm |
10.73 kg / 23.65 LBS
2 950 Gs
|
1.61 kg / 3.55 LBS
1609 g / 15.8 N
|
9.66 kg / 21.29 LBS
~0 Gs
|
| 10 mm |
7.19 kg / 15.84 LBS
2 414 Gs
|
1.08 kg / 2.38 LBS
1078 g / 10.6 N
|
6.47 kg / 14.26 LBS
~0 Gs
|
| 20 mm |
2.73 kg / 6.01 LBS
1 487 Gs
|
0.41 kg / 0.90 LBS
409 g / 4.0 N
|
2.46 kg / 5.41 LBS
~0 Gs
|
| 50 mm |
0.18 kg / 0.39 LBS
379 Gs
|
0.03 kg / 0.06 LBS
27 g / 0.3 N
|
0.16 kg / 0.35 LBS
~0 Gs
|
| 60 mm |
0.08 kg / 0.18 LBS
259 Gs
|
0.01 kg / 0.03 LBS
12 g / 0.1 N
|
0.07 kg / 0.16 LBS
~0 Gs
|
| 70 mm |
0.04 kg / 0.09 LBS
183 Gs
|
0.01 kg / 0.01 LBS
6 g / 0.1 N
|
0.04 kg / 0.08 LBS
~0 Gs
|
| 80 mm |
0.02 kg / 0.05 LBS
133 Gs
|
0.00 kg / 0.01 LBS
3 g / 0.0 N
|
0.02 kg / 0.04 LBS
~0 Gs
|
| 90 mm |
0.01 kg / 0.03 LBS
99 Gs
|
0.00 kg / 0.00 LBS
2 g / 0.0 N
|
0.01 kg / 0.02 LBS
~0 Gs
|
| 100 mm |
0.01 kg / 0.02 LBS
76 Gs
|
0.00 kg / 0.00 LBS
1 g / 0.0 N
|
0.00 kg / 0.00 LBS
~0 Gs
|
Table 7: Hazards (electronics) - precautionary measures
MPL 40x20x4x2[7/3.5] / N38
| Object / Device | Limit (Gauss) / mT | Safe distance |
|---|---|---|
| Pacemaker | 5 Gs (0.5 mT) | 10.5 cm |
| Hearing aid | 10 Gs (1.0 mT) | 8.5 cm |
| Mechanical watch | 20 Gs (2.0 mT) | 6.5 cm |
| Phone / Smartphone | 40 Gs (4.0 mT) | 5.0 cm |
| Remote | 50 Gs (5.0 mT) | 4.5 cm |
| Payment card | 400 Gs (40.0 mT) | 2.0 cm |
| HDD hard drive | 600 Gs (60.0 mT) | 1.5 cm |
Table 8: Collisions (kinetic energy) - collision effects
MPL 40x20x4x2[7/3.5] / N38
| Start from (mm) | Speed (km/h) | Energy (J) | Predicted outcome |
|---|---|---|---|
| 10 mm |
19.91 km/h
(5.53 m/s)
|
0.37 J | |
| 30 mm |
31.03 km/h
(8.62 m/s)
|
0.89 J | |
| 50 mm |
39.93 km/h
(11.09 m/s)
|
1.48 J | |
| 100 mm |
56.45 km/h
(15.68 m/s)
|
2.95 J |
Table 9: Surface protection spec
MPL 40x20x4x2[7/3.5] / 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)
MPL 40x20x4x2[7/3.5] / N38
| Parameter | Value | SI Unit / Description |
|---|---|---|
| Magnetic Flux | 15 299 Mx | 153.0 µWb |
| Pc Coefficient | 0.19 | Low (Flat) |
Table 11: Hydrostatics and buoyancy
MPL 40x20x4x2[7/3.5] / N38
| Environment | Effective steel pull | Effect |
|---|---|---|
| Air (land) | 7.52 kg | Standard |
| Water (riverbed) |
8.61 kg
(+1.09 kg buoyancy gain)
|
+14.5% |
1. Vertical hold
*Warning: On a vertical surface, the magnet holds just a fraction of its max power.
2. Steel thickness impact
*Thin steel (e.g. computer case) significantly limits the holding force.
3. Thermal stability
*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) = 0.19
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.
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% |
Sustainability
| recyclability (EoL) | 100% |
| recycled raw materials | ~10% (pre-cons) |
| carbon footprint | low / zredukowany |
| waste code (EWC) | 16 02 16 |
Other products
Strengths and weaknesses of Nd2Fe14B magnets.
Pros
- They do not lose strength, even over nearly 10 years – the drop in power is only ~1% (theoretically),
- They are extremely resistant to demagnetization induced by presence of other magnetic fields,
- The use of an refined finish of noble metals (nickel, gold, silver) causes the element to present itself better,
- Magnets exhibit extremely high magnetic induction on the active area,
- Thanks to resistance to high temperature, they can operate (depending on the form) even at temperatures up to 230°C and higher...
- In view of the potential of precise molding and adaptation to specialized requirements, magnetic components can be created in a broad palette of forms and dimensions, which amplifies use scope,
- Significant place in electronics industry – they are utilized in HDD drives, electric drive systems, precision medical tools, and technologically advanced constructions.
- Compactness – despite small sizes they provide effective action, making them ideal for precision applications
Limitations
- Brittleness is one of their disadvantages. Upon strong impact they can fracture. We recommend keeping them in a strong case, which not only protects them against impacts but also raises their durability
- When exposed to high temperature, neodymium magnets experience a drop in force. 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 during using outdoors, we suggest using waterproof magnets made of rubber, plastic or other material resistant to moisture
- Limited possibility of creating threads in the magnet and complicated forms - recommended is a housing - mounting mechanism.
- Possible danger to health – tiny shards of magnets are risky, in case of ingestion, which gains importance in the aspect of protecting the youngest. Additionally, small components of these products can disrupt the diagnostic process medical when they are in the body.
- Higher cost of purchase is a significant factor to consider compared to ceramic magnets, especially in budget applications
Lifting parameters
Maximum magnetic pulling force – what affects it?
- using a sheet made of low-carbon steel, acting as a circuit closing element
- with a cross-section minimum 10 mm
- with a plane perfectly flat
- under conditions of gap-free contact (metal-to-metal)
- under perpendicular application of breakaway force (90-degree angle)
- at ambient temperature room level
Determinants of lifting force in real conditions
- Distance (between the magnet and the metal), since even a microscopic clearance (e.g. 0.5 mm) can cause a drastic drop in force by up to 50% (this also applies to paint, rust or dirt).
- Force direction – remember that the magnet has greatest strength perpendicularly. Under shear forces, the capacity drops drastically, often to levels of 20-30% of the maximum value.
- Plate thickness – too thin sheet causes magnetic saturation, causing part of the flux to be lost to the other side.
- Steel grade – the best choice is high-permeability steel. Cast iron may generate lower lifting capacity.
- Plate texture – ground elements guarantee perfect abutment, which improves field saturation. Uneven metal reduce efficiency.
- Temperature – temperature increase causes a temporary drop of force. Check the maximum operating temperature for a given model.
Lifting capacity was determined using a steel plate with a smooth surface of suitable thickness (min. 20 mm), under perpendicular pulling force, whereas under shearing force the holding force is lower. Moreover, even a minimal clearance between the magnet’s surface and the plate reduces the holding force.
Precautions when working with NdFeB magnets
ICD Warning
For implant holders: Powerful magnets affect medical devices. Keep at least 30 cm distance or ask another person to handle the magnets.
Adults only
Adult use only. Small elements pose a choking risk, causing intestinal necrosis. Store away from kids and pets.
Eye protection
Despite metallic appearance, the material is brittle and not impact-resistant. Avoid impacts, as the magnet may crumble into sharp, dangerous pieces.
Maximum temperature
Regular neodymium magnets (N-type) lose magnetization when the temperature surpasses 80°C. Damage is permanent.
Fire risk
Dust created during cutting of magnets is combustible. Do not drill into magnets without proper cooling and knowledge.
Do not underestimate power
Handle with care. Neodymium magnets attract from a distance and connect with massive power, often faster than you can react.
Sensitization to coating
Some people experience a contact allergy to nickel, which is the standard coating for neodymium magnets. Prolonged contact may cause an allergic reaction. We strongly advise use protective gloves.
Pinching danger
Large magnets can smash fingers in a fraction of a second. Under no circumstances put your hand between two strong magnets.
Electronic hazard
Data protection: Strong magnets can ruin payment cards and delicate electronics (pacemakers, medical aids, timepieces).
Phone sensors
Note: neodymium magnets generate a field that confuses precision electronics. Keep a safe distance from your mobile, device, and GPS.
