Strong neodymium magnets: discs and cylinders

Want to buy really powerful magnets? Our range includes rich assortment of disc, cylindrical and ring magnets. Best choice for home use, garage and industrial tasks. See products in stock.

discover magnet catalog

Magnets for underwater searches

Start your adventure involving underwater treasure hunting! Our specialized grips (F200, F400) provide grip certainty and huge lifting capacity. Solid, corrosion-resistant housing and reinforced ropes will perform in any water.

choose searching equipment

Industrial magnetic grips mounting

Professional solutions for mounting non-invasive. Threaded mounts (M8, M10, M12) provide quick improvement of work on warehouses. Perfect for installing lighting, detectors and ads.

check available threads

🚚 Order by 14:00 – we'll ship today!

Dhit sp. z o.o.
Product available Ships in 2 days

MPL 30x20x5 / N38 - lamellar magnet

lamellar magnet

Catalog no 020143

GTIN/EAN: 5906301811497

5.00

length

30 mm [±0,1 mm]

Width

20 mm [±0,1 mm]

Height

5 mm [±0,1 mm]

Weight

22.5 g

Magnetization Direction

↑ axial

Load capacity

8.86 kg / 86.90 N

Magnetic Induction

220.03 mT / 2200 Gs

Coating

[NiCuNi] Nickel

9.10 with VAT / pcs + price for transport

7.40 ZŁ net + 23% VAT / pcs

bulk discounts:

Need more?

price from 1 pcs
7.40 ZŁ
9.10 ZŁ
price from 100 pcs
6.96 ZŁ
8.56 ZŁ
price from 350 pcs
6.51 ZŁ
8.01 ZŁ
Need advice?

Give us a call +48 22 499 98 98 otherwise let us know through contact form through our site.
Lifting power along with shape of a neodymium magnet can be reviewed using our our magnetic calculator.

Same-day shipping for orders placed before 14:00.

Detailed specification - MPL 30x20x5 / N38 - lamellar magnet

Specification / characteristics - MPL 30x20x5 / N38 - lamellar magnet

properties
properties values
Cat. no. 020143
GTIN/EAN 5906301811497
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 30 mm [±0,1 mm]
Width 20 mm [±0,1 mm]
Height 5 mm [±0,1 mm]
Weight 22.5 g
Magnetization Direction ↑ axial
Load capacity ~ ? 8.86 kg / 86.90 N
Magnetic Induction ~ ? 220.03 mT / 2200 Gs
Coating [NiCuNi] Nickel
Manufacturing Tolerance ±0.1 mm

Magnetic properties of material N38

Specification / characteristics MPL 30x20x5 / 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 simulation of the assembly - data

Presented information constitute the outcome of a mathematical analysis. Values are based on models for the class Nd2Fe14B. Real-world parameters might slightly differ from theoretical values. Treat these data as a preliminary roadmap for designers.

Table 1: Static force (pull vs distance) - power drop
MPL 30x20x5 / N38

Distance (mm) Induction (Gauss) / mT Pull Force (kg/lbs/g/N) Risk Status
0 mm 2200 Gs
220.0 mT
8.86 kg / 19.53 lbs
8860.0 g / 86.9 N
strong
1 mm 2092 Gs
209.2 mT
8.01 kg / 17.67 lbs
8013.9 g / 78.6 N
strong
2 mm 1961 Gs
196.1 mT
7.04 kg / 15.53 lbs
7042.1 g / 69.1 N
strong
3 mm 1817 Gs
181.7 mT
6.04 kg / 13.32 lbs
6041.8 g / 59.3 N
strong
5 mm 1516 Gs
151.6 mT
4.21 kg / 9.28 lbs
4209.6 g / 41.3 N
strong
10 mm 892 Gs
89.2 mT
1.46 kg / 3.21 lbs
1456.2 g / 14.3 N
low risk
15 mm 519 Gs
51.9 mT
0.49 kg / 1.09 lbs
492.4 g / 4.8 N
low risk
20 mm 313 Gs
31.3 mT
0.18 kg / 0.40 lbs
179.8 g / 1.8 N
low risk
30 mm 132 Gs
13.2 mT
0.03 kg / 0.07 lbs
31.9 g / 0.3 N
low risk
50 mm 37 Gs
3.7 mT
0.00 kg / 0.01 lbs
2.5 g / 0.0 N
low risk

Table 2: Vertical force (wall)
MPL 30x20x5 / N38

Distance (mm) Friction coefficient Pull Force (kg/lbs/g/N)
0 mm Stal (~0.2) 1.77 kg / 3.91 lbs
1772.0 g / 17.4 N
1 mm Stal (~0.2) 1.60 kg / 3.53 lbs
1602.0 g / 15.7 N
2 mm Stal (~0.2) 1.41 kg / 3.10 lbs
1408.0 g / 13.8 N
3 mm Stal (~0.2) 1.21 kg / 2.66 lbs
1208.0 g / 11.9 N
5 mm Stal (~0.2) 0.84 kg / 1.86 lbs
842.0 g / 8.3 N
10 mm Stal (~0.2) 0.29 kg / 0.64 lbs
292.0 g / 2.9 N
15 mm Stal (~0.2) 0.10 kg / 0.22 lbs
98.0 g / 1.0 N
20 mm Stal (~0.2) 0.04 kg / 0.08 lbs
36.0 g / 0.4 N
30 mm Stal (~0.2) 0.01 kg / 0.01 lbs
6.0 g / 0.1 N
50 mm Stal (~0.2) 0.00 kg / 0.00 lbs
0.0 g / 0.0 N

Table 3: Wall mounting (shearing) - behavior on slippery surfaces
MPL 30x20x5 / N38

Surface type Friction coefficient / % Mocy Max load (kg/lbs/g/N)
Raw steel
µ = 0.3 30% Nominalnej Siły
2.66 kg / 5.86 lbs
2658.0 g / 26.1 N
Painted steel (standard)
µ = 0.2 20% Nominalnej Siły
1.77 kg / 3.91 lbs
1772.0 g / 17.4 N
Oily/slippery steel
µ = 0.1 10% Nominalnej Siły
0.89 kg / 1.95 lbs
886.0 g / 8.7 N
Magnet with anti-slip rubber
µ = 0.5 50% Nominalnej Siły
4.43 kg / 9.77 lbs
4430.0 g / 43.5 N

Table 4: Steel thickness (substrate influence) - sheet metal selection
MPL 30x20x5 / N38

Steel thickness (mm) % power Real pull force (kg/lbs/g/N)
0.5 mm
10%
0.89 kg / 1.95 lbs
886.0 g / 8.7 N
1 mm
25%
2.22 kg / 4.88 lbs
2215.0 g / 21.7 N
2 mm
50%
4.43 kg / 9.77 lbs
4430.0 g / 43.5 N
3 mm
75%
6.65 kg / 14.65 lbs
6645.0 g / 65.2 N
5 mm
100%
8.86 kg / 19.53 lbs
8860.0 g / 86.9 N
10 mm
100%
8.86 kg / 19.53 lbs
8860.0 g / 86.9 N
11 mm
100%
8.86 kg / 19.53 lbs
8860.0 g / 86.9 N
12 mm
100%
8.86 kg / 19.53 lbs
8860.0 g / 86.9 N

Table 5: Thermal resistance (material behavior) - thermal limit
MPL 30x20x5 / N38

Ambient temp. (°C) Power loss Remaining pull (kg/lbs/g/N) Status
20 °C 0.0% 8.86 kg / 19.53 lbs
8860.0 g / 86.9 N
OK
40 °C -2.2% 8.67 kg / 19.10 lbs
8665.1 g / 85.0 N
OK
60 °C -4.4% 8.47 kg / 18.67 lbs
8470.2 g / 83.1 N
80 °C -6.6% 8.28 kg / 18.24 lbs
8275.2 g / 81.2 N
100 °C -28.8% 6.31 kg / 13.91 lbs
6308.3 g / 61.9 N

Table 6: Magnet-Magnet interaction (repulsion) - field range
MPL 30x20x5 / N38

Gap (mm) Attraction (kg/lbs) (N-S) Lateral Force (kg/lbs/g/N) Repulsion (kg/lbs) (N-N)
0 mm 17.90 kg / 39.47 lbs
3 715 Gs
2.69 kg / 5.92 lbs
2685 g / 26.3 N
N/A
1 mm 17.10 kg / 37.69 lbs
4 300 Gs
2.56 kg / 5.65 lbs
2565 g / 25.2 N
15.39 kg / 33.92 lbs
~0 Gs
2 mm 16.19 kg / 35.70 lbs
4 184 Gs
2.43 kg / 5.35 lbs
2429 g / 23.8 N
14.57 kg / 32.13 lbs
~0 Gs
3 mm 15.23 kg / 33.57 lbs
4 058 Gs
2.28 kg / 5.04 lbs
2284 g / 22.4 N
13.71 kg / 30.22 lbs
~0 Gs
5 mm 13.22 kg / 29.14 lbs
3 780 Gs
1.98 kg / 4.37 lbs
1982 g / 19.4 N
11.89 kg / 26.22 lbs
~0 Gs
10 mm 8.51 kg / 18.75 lbs
3 033 Gs
1.28 kg / 2.81 lbs
1276 g / 12.5 N
7.66 kg / 16.88 lbs
~0 Gs
20 mm 2.94 kg / 6.49 lbs
1 784 Gs
0.44 kg / 0.97 lbs
441 g / 4.3 N
2.65 kg / 5.84 lbs
~0 Gs
50 mm 0.15 kg / 0.32 lbs
398 Gs
0.02 kg / 0.05 lbs
22 g / 0.2 N
0.13 kg / 0.29 lbs
~0 Gs
60 mm 0.06 kg / 0.14 lbs
264 Gs
0.01 kg / 0.02 lbs
10 g / 0.1 N
0.06 kg / 0.13 lbs
~0 Gs
70 mm 0.03 kg / 0.07 lbs
183 Gs
0.00 kg / 0.01 lbs
5 g / 0.0 N
0.03 kg / 0.06 lbs
~0 Gs
80 mm 0.02 kg / 0.04 lbs
131 Gs
0.00 kg / 0.01 lbs
2 g / 0.0 N
0.01 kg / 0.03 lbs
~0 Gs
90 mm 0.01 kg / 0.02 lbs
97 Gs
0.00 kg / 0.00 lbs
1 g / 0.0 N
0.00 kg / 0.00 lbs
~0 Gs
100 mm 0.00 kg / 0.01 lbs
73 Gs
0.00 kg / 0.00 lbs
1 g / 0.0 N
0.00 kg / 0.00 lbs
~0 Gs

Table 7: Protective zones (implants) - precautionary measures
MPL 30x20x5 / 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
Timepiece 20 Gs (2.0 mT) 6.5 cm
Phone / Smartphone 40 Gs (4.0 mT) 5.0 cm
Car key 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: Dynamics (kinetic energy) - warning
MPL 30x20x5 / N38

Start from (mm) Speed (km/h) Energy (J) Predicted outcome
10 mm 21.97 km/h
(6.10 m/s)
0.42 J
30 mm 34.74 km/h
(9.65 m/s)
1.05 J
50 mm 44.76 km/h
(12.43 m/s)
1.74 J
100 mm 63.29 km/h
(17.58 m/s)
3.48 J

Table 9: Coating parameters (durability)
MPL 30x20x5 / 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)
MPL 30x20x5 / N38

Parameter Value SI Unit / Description
Magnetic Flux 14 969 Mx 149.7 µWb
Pc Coefficient 0.26 Low (Flat)

Table 11: Underwater work (magnet fishing)
MPL 30x20x5 / N38

Environment Effective steel pull Effect
Air (land) 8.86 kg Standard
Water (riverbed) 10.14 kg
(+1.28 kg buoyancy gain)
+14.5%
Rust risk: Standard nickel requires drying after every contact with moisture; lack of maintenance will lead to rust spots.
1. Wall mount (shear)

*Warning: On a vertical surface, the magnet retains merely ~20% of its nominal pull.

2. Plate thickness effect

*Thin steel (e.g. 0.5mm PC case) drastically limits the holding force.

3. Thermal stability

*For standard magnets, the safety 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.

Technical and environmental data
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%
Sustainability
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: 020143-2026
Quick Unit Converter
Force (pull)

Magnetic Field

Check out also deals

This product is a very powerful magnet in the shape of a plate made of NdFeB material, which, with dimensions of 30x20x5 mm and a weight of 22.5 g, guarantees the highest quality connection. As a magnetic bar with high power (approx. 8.86 kg), this product is available immediately from our warehouse in Poland. 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 8.86 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 generators and material handling systems. They work great as fasteners under tiles, wood, or glass. Their rectangular shape facilitates precise gluing into milled sockets in wood or plastic.
For mounting flat magnets MPL 30x20x5 / N38, it is best to use strong epoxy glues (e.g., UHU Endfest, Distal), which ensure a durable bond with metal or plastic. Double-sided tape cushions vibrations, which is an advantage when mounting in moving elements. Remember to clean and degrease the magnet surface before gluing, which significantly increases the adhesion of the glue to the nickel coating.
Standardly, the MPL 30x20x5 / N38 model is magnetized axially (dimension 5 mm), which means that the N and S poles are located on its largest, flat surfaces. Thanks to this, it works best when "sticking" to sheet metal or another magnet with a large surface area. Such a pole arrangement ensures maximum holding capacity when pressing against the sheet, creating a closed magnetic circuit.
This model is characterized by dimensions 30x20x5 mm, which, at a weight of 22.5 g, makes it an element with high energy density. The key parameter here is the holding force amounting to approximately 8.86 kg (force ~86.90 N), which, with such a flat shape, proves the high grade of the material. The protective [NiCuNi] coating secures the magnet against corrosion.

Advantages and disadvantages of Nd2Fe14B magnets.

Pros

Apart from their superior magnetic energy, neodymium magnets have these key benefits:
  • They have stable power, and over nearly ten years their performance decreases symbolically – ~1% (in testing),
  • They are resistant to demagnetization induced by external magnetic fields,
  • Thanks to the glossy finish, the surface of nickel, gold, or silver-plated gives an modern appearance,
  • Magnetic induction on the working part of the magnet turns out to be exceptional,
  • Through (appropriate) combination of ingredients, they can achieve high thermal strength, enabling functioning at temperatures reaching 230°C and above...
  • Thanks to the ability of precise shaping and adaptation to unique solutions, NdFeB magnets can be modeled in a wide range of forms and dimensions, which increases their versatility,
  • Fundamental importance in modern technologies – they find application in computer drives, drive modules, advanced medical instruments, also multitasking production systems.
  • Thanks to their power density, small magnets offer high operating force, occupying minimum space,

Weaknesses

Drawbacks and weaknesses of neodymium magnets and ways of using them
  • To avoid cracks under impact, we suggest using special steel housings. Such a solution protects the magnet and simultaneously increases its durability.
  • We warn that neodymium magnets can reduce their power at high temperatures. To prevent this, we advise our specialized [AH] magnets, which work effectively even at 230°C.
  • Due to the susceptibility of magnets to corrosion in a humid environment, we recommend using waterproof magnets made of rubber, plastic or other material stable to moisture, when using outdoors
  • Due to limitations in creating threads and complex shapes in magnets, we recommend using cover - magnetic holder.
  • Potential hazard resulting from small fragments of magnets are risky, if 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 when they are in the body.
  • Due to complex production process, their price is higher than average,

Holding force characteristics

Optimal lifting capacity of a neodymium magnetwhat it depends on?

Breakaway force is the result of a measurement for ideal contact conditions, taking into account:
  • using a plate made of high-permeability steel, serving as a circuit closing element
  • with a thickness of at least 10 mm
  • characterized by lack of roughness
  • without the slightest insulating layer between the magnet and steel
  • for force acting at a right angle (in the magnet axis)
  • in stable room temperature

Key elements affecting lifting force

Holding efficiency is affected by specific conditions, mainly (from most important):
  • Space between magnet and steel – every millimeter of distance (caused e.g. by varnish or unevenness) significantly weakens the pulling force, often by half at just 0.5 mm.
  • Force direction – catalog parameter refers to detachment vertically. When attempting to slide, the magnet exhibits much less (often approx. 20-30% of nominal force).
  • Base massiveness – too thin plate does not accept the full field, 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.
  • Surface structure – the smoother and more polished the plate, the better the adhesion and higher the lifting capacity. Unevenness creates an air distance.
  • Operating temperature – neodymium magnets have a sensitivity to temperature. At higher temperatures they are weaker, and in frost gain strength (up to a certain limit).

Lifting capacity testing was carried out on plates with a smooth surface of suitable thickness, under a perpendicular pulling force, however under parallel forces the lifting capacity is smaller. Additionally, even a slight gap between the magnet’s surface and the plate decreases the lifting capacity.

Safe handling of neodymium magnets
Allergic reactions

A percentage of the population experience a hypersensitivity to Ni, which is the common plating for neodymium magnets. Frequent touching might lead to an allergic reaction. We suggest use safety gloves.

Data carriers

Avoid bringing magnets close to a wallet, laptop, or screen. The magnetic field can permanently damage these devices and wipe information from cards.

Health Danger

People with a pacemaker must maintain an large gap from magnets. The magnetism can disrupt the functioning of the life-saving device.

Pinching danger

Protect your hands. Two powerful magnets will snap together immediately with a force of massive weight, destroying anything in their path. Be careful!

Choking Hazard

Strictly store magnets out of reach of children. Risk of swallowing is high, and the effects of magnets connecting inside the body are life-threatening.

Caution required

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

Eye protection

Neodymium magnets are ceramic materials, meaning they are fragile like glass. Clashing of two magnets leads to them breaking into small pieces.

Mechanical processing

Machining of NdFeB material carries a risk of fire risk. Magnetic powder oxidizes rapidly with oxygen and is difficult to extinguish.

Heat sensitivity

Control the heat. Exposing the magnet to high heat will permanently weaken its properties and pulling force.

GPS Danger

A powerful magnetic field disrupts the operation of magnetometers in smartphones and navigation systems. Maintain magnets near a smartphone to prevent breaking the sensors.

Warning! Want to know more? Check our post: Why are neodymium magnets dangerous?
Dhit sp. z o.o.

e-mail: bok@dhit.pl

tel: +48 888 99 98 98