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MPL 40x10x4 / N38 - lamellar magnet

lamellar magnet

Catalog no 020150

GTIN/EAN: 5906301811565

5.00

length

40 mm [±0,1 mm]

Width

10 mm [±0,1 mm]

Height

4 mm [±0,1 mm]

Weight

12 g

Magnetization Direction

↑ axial

Load capacity

9.31 kg / 91.33 N

Magnetic Induction

275.57 mT / 2756 Gs

Coating

[NiCuNi] Nickel

4.87 with VAT / pcs + price for transport

3.96 ZŁ net + 23% VAT / pcs

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Technical - MPL 40x10x4 / N38 - lamellar magnet

Specification / characteristics - MPL 40x10x4 / N38 - lamellar magnet

properties
properties values
Cat. no. 020150
GTIN/EAN 5906301811565
Production/Distribution Dhit sp. z o.o.
ul. Zielona 14 05-850 Ożarów Mazowiecki PL
Country of origin Poland / China / Germany
Customs code 85059029
length 40 mm [±0,1 mm]
Width 10 mm [±0,1 mm]
Height 4 mm [±0,1 mm]
Weight 12 g
Magnetization Direction ↑ axial
Load capacity ~ ? 9.31 kg / 91.33 N
Magnetic Induction ~ ? 275.57 mT / 2756 Gs
Coating [NiCuNi] Nickel
Manufacturing Tolerance ±0.1 mm

Magnetic properties of material N38

Specification / characteristics MPL 40x10x4 / N38 - lamellar 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

Physical analysis of the assembly - technical parameters

The following values represent the direct effect of a engineering analysis. Values are based on models for the material Nd2Fe14B. Operational conditions might slightly differ. Please consider these data as a preliminary roadmap during assembly planning.

Table 1: Static force (pull vs gap) - power drop
MPL 40x10x4 / N38

Distance (mm) Induction (Gauss) / mT Pull Force (kg/lbs/g/N) Risk Status
0 mm 2755 Gs
275.5 mT
9.31 kg / 20.53 lbs
9310.0 g / 91.3 N
strong
1 mm 2413 Gs
241.3 mT
7.14 kg / 15.75 lbs
7143.1 g / 70.1 N
strong
2 mm 2044 Gs
204.4 mT
5.13 kg / 11.31 lbs
5128.9 g / 50.3 N
strong
3 mm 1703 Gs
170.3 mT
3.56 kg / 7.85 lbs
3559.5 g / 34.9 N
strong
5 mm 1173 Gs
117.3 mT
1.69 kg / 3.72 lbs
1688.2 g / 16.6 N
safe
10 mm 522 Gs
52.2 mT
0.33 kg / 0.74 lbs
334.9 g / 3.3 N
safe
15 mm 277 Gs
27.7 mT
0.09 kg / 0.21 lbs
94.2 g / 0.9 N
safe
20 mm 163 Gs
16.3 mT
0.03 kg / 0.07 lbs
32.8 g / 0.3 N
safe
30 mm 69 Gs
6.9 mT
0.01 kg / 0.01 lbs
5.8 g / 0.1 N
safe
50 mm 19 Gs
1.9 mT
0.00 kg / 0.00 lbs
0.5 g / 0.0 N
safe

Table 2: Shear force (wall)
MPL 40x10x4 / N38

Distance (mm) Friction coefficient Pull Force (kg/lbs/g/N)
0 mm Stal (~0.2) 1.86 kg / 4.11 lbs
1862.0 g / 18.3 N
1 mm Stal (~0.2) 1.43 kg / 3.15 lbs
1428.0 g / 14.0 N
2 mm Stal (~0.2) 1.03 kg / 2.26 lbs
1026.0 g / 10.1 N
3 mm Stal (~0.2) 0.71 kg / 1.57 lbs
712.0 g / 7.0 N
5 mm Stal (~0.2) 0.34 kg / 0.75 lbs
338.0 g / 3.3 N
10 mm Stal (~0.2) 0.07 kg / 0.15 lbs
66.0 g / 0.6 N
15 mm Stal (~0.2) 0.02 kg / 0.04 lbs
18.0 g / 0.2 N
20 mm Stal (~0.2) 0.01 kg / 0.01 lbs
6.0 g / 0.1 N
30 mm Stal (~0.2) 0.00 kg / 0.00 lbs
2.0 g / 0.0 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 40x10x4 / N38

Surface type Friction coefficient / % Mocy Max load (kg/lbs/g/N)
Raw steel
µ = 0.3 30% Nominalnej Siły
2.79 kg / 6.16 lbs
2793.0 g / 27.4 N
Painted steel (standard)
µ = 0.2 20% Nominalnej Siły
1.86 kg / 4.11 lbs
1862.0 g / 18.3 N
Oily/slippery steel
µ = 0.1 10% Nominalnej Siły
0.93 kg / 2.05 lbs
931.0 g / 9.1 N
Magnet with anti-slip rubber
µ = 0.5 50% Nominalnej Siły
4.66 kg / 10.26 lbs
4655.0 g / 45.7 N

Table 4: Material efficiency (saturation) - sheet metal selection
MPL 40x10x4 / N38

Steel thickness (mm) % power Real pull force (kg/lbs/g/N)
0.5 mm
10%
0.93 kg / 2.05 lbs
931.0 g / 9.1 N
1 mm
25%
2.33 kg / 5.13 lbs
2327.5 g / 22.8 N
2 mm
50%
4.66 kg / 10.26 lbs
4655.0 g / 45.7 N
3 mm
75%
6.98 kg / 15.39 lbs
6982.5 g / 68.5 N
5 mm
100%
9.31 kg / 20.53 lbs
9310.0 g / 91.3 N
10 mm
100%
9.31 kg / 20.53 lbs
9310.0 g / 91.3 N
11 mm
100%
9.31 kg / 20.53 lbs
9310.0 g / 91.3 N
12 mm
100%
9.31 kg / 20.53 lbs
9310.0 g / 91.3 N

Table 5: Working in heat (material behavior) - power drop
MPL 40x10x4 / N38

Ambient temp. (°C) Power loss Remaining pull (kg/lbs/g/N) Status
20 °C 0.0% 9.31 kg / 20.53 lbs
9310.0 g / 91.3 N
OK
40 °C -2.2% 9.11 kg / 20.07 lbs
9105.2 g / 89.3 N
OK
60 °C -4.4% 8.90 kg / 19.62 lbs
8900.4 g / 87.3 N
80 °C -6.6% 8.70 kg / 19.17 lbs
8695.5 g / 85.3 N
100 °C -28.8% 6.63 kg / 14.61 lbs
6628.7 g / 65.0 N

Table 6: Two magnets (repulsion) - forces in the system
MPL 40x10x4 / N38

Gap (mm) Attraction (kg/lbs) (N-S) Shear Force (kg/lbs/g/N) Repulsion (kg/lbs) (N-N)
0 mm 18.71 kg / 41.25 lbs
4 164 Gs
2.81 kg / 6.19 lbs
2807 g / 27.5 N
N/A
1 mm 16.57 kg / 36.53 lbs
5 185 Gs
2.49 kg / 5.48 lbs
2486 g / 24.4 N
14.91 kg / 32.88 lbs
~0 Gs
2 mm 14.36 kg / 31.65 lbs
4 826 Gs
2.15 kg / 4.75 lbs
2153 g / 21.1 N
12.92 kg / 28.48 lbs
~0 Gs
3 mm 12.24 kg / 26.98 lbs
4 455 Gs
1.84 kg / 4.05 lbs
1836 g / 18.0 N
11.01 kg / 24.28 lbs
~0 Gs
5 mm 8.61 kg / 18.98 lbs
3 737 Gs
1.29 kg / 2.85 lbs
1291 g / 12.7 N
7.75 kg / 17.08 lbs
~0 Gs
10 mm 3.39 kg / 7.48 lbs
2 346 Gs
0.51 kg / 1.12 lbs
509 g / 5.0 N
3.05 kg / 6.73 lbs
~0 Gs
20 mm 0.67 kg / 1.48 lbs
1 045 Gs
0.10 kg / 0.22 lbs
101 g / 1.0 N
0.61 kg / 1.34 lbs
~0 Gs
50 mm 0.03 kg / 0.06 lbs
207 Gs
0.00 kg / 0.01 lbs
4 g / 0.0 N
0.02 kg / 0.05 lbs
~0 Gs
60 mm 0.01 kg / 0.03 lbs
138 Gs
0.00 kg / 0.00 lbs
2 g / 0.0 N
0.01 kg / 0.02 lbs
~0 Gs
70 mm 0.01 kg / 0.01 lbs
96 Gs
0.00 kg / 0.00 lbs
1 g / 0.0 N
0.00 kg / 0.00 lbs
~0 Gs
80 mm 0.00 kg / 0.01 lbs
69 Gs
0.00 kg / 0.00 lbs
0 g / 0.0 N
0.00 kg / 0.00 lbs
~0 Gs
90 mm 0.00 kg / 0.00 lbs
51 Gs
0.00 kg / 0.00 lbs
0 g / 0.0 N
0.00 kg / 0.00 lbs
~0 Gs
100 mm 0.00 kg / 0.00 lbs
39 Gs
0.00 kg / 0.00 lbs
0 g / 0.0 N
0.00 kg / 0.00 lbs
~0 Gs

Table 7: Protective zones (implants) - precautionary measures
MPL 40x10x4 / N38

Object / Device Limit (Gauss) / mT Safe distance
Pacemaker 5 Gs (0.5 mT) 8.5 cm
Hearing aid 10 Gs (1.0 mT) 6.5 cm
Timepiece 20 Gs (2.0 mT) 5.0 cm
Phone / Smartphone 40 Gs (4.0 mT) 4.0 cm
Remote 50 Gs (5.0 mT) 3.5 cm
Payment card 400 Gs (40.0 mT) 1.5 cm
HDD hard drive 600 Gs (60.0 mT) 1.0 cm

Table 8: Collisions (cracking risk) - collision effects
MPL 40x10x4 / N38

Start from (mm) Speed (km/h) Energy (J) Predicted outcome
10 mm 28.72 km/h
(7.98 m/s)
0.38 J
30 mm 48.67 km/h
(13.52 m/s)
1.10 J
50 mm 62.82 km/h
(17.45 m/s)
1.83 J
100 mm 88.83 km/h
(24.68 m/s)
3.65 J

Table 9: Anti-corrosion coating durability
MPL 40x10x4 / 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: Construction data (Pc)
MPL 40x10x4 / N38

Parameter Value SI Unit / Description
Magnetic Flux 9 840 Mx 98.4 µWb
Pc Coefficient 0.26 Low (Flat)

Table 11: Underwater work (magnet fishing)
MPL 40x10x4 / N38

Environment Effective steel pull Effect
Air (land) 9.31 kg Standard
Water (riverbed) 10.66 kg
(+1.35 kg buoyancy gain)
+14.5%
Rust risk: Remember to wipe the magnet thoroughly after removing it from water and apply a protective layer (e.g., oil) to avoid corrosion.
1. Vertical hold

*Caution: On a vertical wall, the magnet holds merely approx. 20-30% of its nominal pull.

2. Efficiency vs thickness

*Thin steel (e.g. computer case) severely limits 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) = 0.26

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
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%
Environmental data
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: 020150-2026
Quick Unit Converter
Pulling force

Field Strength

View also proposals

This product is an extremely strong plate magnet made of NdFeB material, which, with dimensions of 40x10x4 mm and a weight of 12 g, guarantees the highest quality connection. This rectangular block with a force of 91.33 N is ready for shipment in 24h, allowing for rapid realization of your project. The durable anti-corrosion layer ensures a long lifespan in a dry environment, protecting the core from oxidation.
Separating block magnets requires a technique based on sliding (moving one relative to the other), rather than forceful pulling apart. Watch your fingers! Magnets with a force of 9.31 kg can pinch very hard and cause hematomas. Using a screwdriver risks destroying the coating and permanently cracking the magnet.
They constitute a key element in the production of wind generators and material handling systems. They work great as invisible mounts under tiles, wood, or glass. Their rectangular shape facilitates precise gluing into milled sockets in wood or plastic.
For mounting flat magnets MPL 40x10x4 / N38, we recommend utilizing strong epoxy glues (e.g., UHU Endfest, Distal), which ensure a durable bond with metal or plastic. For lighter applications or mounting on smooth surfaces, branded foam tape (e.g., 3M VHB) will work, provided the surface is perfectly degreased. Remember to roughen and wash the magnet surface before gluing, which significantly increases the adhesion of the glue to the nickel coating.
The magnetic axis runs through the shortest dimension, which is typical for gripper magnets. In practice, this means that this magnet has the greatest attraction force on its main planes (40x10 mm), which is ideal for flat mounting. This is the most popular configuration for block magnets used in separators and holders.
The presented product is a neodymium magnet with precisely defined parameters: 40 mm (length), 10 mm (width), and 4 mm (thickness). It is a magnetic block with dimensions 40x10x4 mm and a self-weight of 12 g, ready to work at temperatures up to 80°C. The product meets the standards for N38 grade magnets.

Pros and cons of neodymium magnets.

Advantages

In addition to their magnetic capacity, neodymium magnets provide the following advantages:
  • Their power is durable, and after around ten years it drops only by ~1% (according to research),
  • Neodymium magnets remain exceptionally resistant to magnetic field loss caused by external magnetic fields,
  • A magnet with a smooth nickel surface is more attractive,
  • Magnets possess huge magnetic induction on the working surface,
  • Through (appropriate) combination of ingredients, they can achieve high thermal resistance, allowing for functioning at temperatures reaching 230°C and above...
  • Due to the ability of flexible molding and customization to individualized requirements, NdFeB magnets can be modeled in a broad palette of forms and dimensions, which expands the range of possible applications,
  • Wide application in future technologies – they serve a role in hard drives, electric drive systems, diagnostic systems, as well as complex engineering applications.
  • Compactness – despite small sizes they generate large force, making them ideal for precision applications

Weaknesses

What to avoid - cons of neodymium magnets: weaknesses and usage proposals
  • They are fragile upon heavy impacts. To avoid cracks, it is worth securing magnets in a protective case. Such protection not only protects the magnet but also increases its resistance to damage
  • Neodymium magnets lose 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 secure oxidation and corrosion.
  • Limited possibility of making threads in the magnet and complicated forms - preferred is casing - mounting mechanism.
  • Potential hazard related to microscopic parts of magnets pose a threat, if swallowed, which becomes key in the context of child health protection. Furthermore, tiny parts of these products are able to be problematic in diagnostics medical in case of swallowing.
  • With large orders the cost of neodymium magnets is economically unviable,

Lifting parameters

Best holding force of the magnet in ideal parameterswhat affects it?

Information about lifting capacity was defined for ideal contact conditions, including:
  • with the use of a sheet made of low-carbon steel, guaranteeing maximum field concentration
  • possessing a thickness of minimum 10 mm to avoid saturation
  • with an polished contact surface
  • without any air gap between the magnet and steel
  • for force applied at a right angle (pull-off, not shear)
  • at ambient temperature room level

Key elements affecting lifting force

It is worth knowing that the working load will differ subject to the following factors, starting with the most relevant:
  • Distance – existence of any layer (rust, tape, air) acts as an insulator, which lowers power steeply (even by 50% at 0.5 mm).
  • Pull-off angle – note that the magnet holds strongest perpendicularly. Under shear forces, the capacity drops drastically, often to levels of 20-30% of the nominal value.
  • Element thickness – to utilize 100% power, the steel must be sufficiently thick. Paper-thin metal limits the attraction force (the magnet "punches through" it).
  • Metal type – not every steel attracts identically. Alloy additives worsen the interaction with the magnet.
  • Smoothness – ideal contact is obtained only on smooth steel. Rough texture create air cushions, reducing force.
  • Temperature – temperature increase results in weakening of force. Check the thermal limit for a given model.

Lifting capacity testing was performed on plates with a smooth surface of optimal thickness, under perpendicular forces, in contrast under attempts to slide the magnet the load capacity is reduced by as much as 75%. In addition, even a small distance between the magnet’s surface and the plate reduces the load capacity.

Safety rules for work with neodymium magnets
Keep away from computers

Powerful magnetic fields can erase data on payment cards, HDDs, and storage devices. Maintain a gap of at least 10 cm.

Health Danger

Warning for patients: Strong magnetic fields disrupt medical devices. Maintain minimum 30 cm distance or request help to work with the magnets.

Power loss in heat

Keep cool. NdFeB magnets are susceptible to temperature. If you need resistance above 80°C, look for HT versions (H, SH, UH).

Allergic reactions

Nickel alert: The Ni-Cu-Ni coating consists of nickel. If redness happens, cease handling magnets and wear gloves.

Phone sensors

Remember: neodymium magnets generate a field that confuses sensitive sensors. Keep a safe distance from your mobile, device, and navigation systems.

Combustion hazard

Combustion risk: Rare earth powder is explosive. Do not process magnets without safety gear as this may cause fire.

Eye protection

Despite metallic appearance, neodymium is brittle and not impact-resistant. Do not hit, as the magnet may crumble into sharp, dangerous pieces.

No play value

Always store magnets away from children. Choking hazard is high, and the consequences of magnets connecting inside the body are fatal.

Respect the power

Handle with care. Neodymium magnets act from a distance and connect with huge force, often quicker than you can move away.

Pinching danger

Watch your fingers. Two large magnets will join immediately with a force of massive weight, crushing anything in their path. Exercise extreme caution!

Security! Details about hazards in the article: Magnet Safety Guide.
Dhit sp. z o.o.

e-mail: bok@dhit.pl

tel: +48 888 99 98 98