Product available Ships tomorrow

MP 25x7.5/4.5x5 / N38 - ring magnet

Name: Dhit sp. z o.o.
Address: Kościuszki 6A, Ożarów Mazowiecki, Poland, 05-850, PL
Telephone: +48 22 499 98 98
Price range: PLN 1-6500
Rating: 5

ring magnet

Catalog no 030194

GTIN/EAN: 5906301812111

5.00

Diameter

25 mm [±0,1 mm]

internal diameter Ø

7.5/4.5 mm [±0,1 mm]

Height

5 mm [±0,1 mm]

Weight

17.81 g

Magnetization Direction

↑ axial

Load capacity

7.72 kg / 75.69 N

Magnetic Induction

230.20 mT / 2302 Gs

Coating

[NiCuNi] Nickel

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8.00 ZŁ with VAT / pcs + price for transport

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Technical of the product - MP 25x7.5/4.5x5 / N38 - ring magnet

Specification / characteristics - MP 25x7.5/4.5x5 / N38 - ring magnet

properties

properties	values
Cat. no.	030194
GTIN/EAN	5906301812111
Production/Distribution	Dhit sp. z o.o. ul. Zielona 14 05-850 Ożarów Mazowiecki PL
Country of origin	Poland / China / Germany
Customs code	85059029
Diameter	25 mm [±0,1 mm]
internal diameter Ø	7.5/4.5 mm [±0,1 mm]
Height	5 mm [±0,1 mm]
Weight	17.81 g
Magnetization Direction	↑ axial
Load capacity ~ ?	7.72 kg / 75.69 N
Magnetic Induction ~ ?	230.20 mT / 2302 Gs
Coating	[NiCuNi] Nickel
Manufacturing Tolerance	±0.1 mm

Magnetic properties of material N38

Specification / characteristics MP 25x7.5/4.5x5 / N38 - ring 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

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 - data

These values constitute the result of a physical analysis. Values rely on models for the class Nd₂Fe₁₄B. Actual parameters might slightly differ from theoretical values. Use these data as a supplementary guide during assembly planning.

Table 1: Static pull force (force vs gap) - power drop
MP 25x7.5/4.5x5 / N38

Distance (mm)	Induction (Gauss) / mT	Pull Force (kg/lbs/g/N)	Risk Status
0 mm	1995 Gs 199.5 mT	7.72 kg / 17.02 LBS 7720.0 g / 75.7 N	strong
1 mm	1906 Gs 190.6 mT	7.05 kg / 15.54 LBS 7049.4 g / 69.2 N	strong
2 mm	1793 Gs 179.3 mT	6.24 kg / 13.75 LBS 6236.8 g / 61.2 N	strong
3 mm	1664 Gs 166.4 mT	5.37 kg / 11.84 LBS 5368.9 g / 52.7 N	strong
5 mm	1385 Gs 138.5 mT	3.72 kg / 8.21 LBS 3722.8 g / 36.5 N	strong
10 mm	788 Gs 78.8 mT	1.20 kg / 2.65 LBS 1203.8 g / 11.8 N	weak grip
15 mm	437 Gs 43.7 mT	0.37 kg / 0.82 LBS 370.3 g / 3.6 N	weak grip
20 mm	253 Gs 25.3 mT	0.12 kg / 0.27 LBS 124.5 g / 1.2 N	weak grip
30 mm	101 Gs 10.1 mT	0.02 kg / 0.04 LBS 19.8 g / 0.2 N	weak grip
50 mm	27 Gs 2.7 mT	0.00 kg / 0.00 LBS 1.4 g / 0.0 N	weak grip

Magnetic force drops sharply with every subsequent millimeter of spacing. Keep in mind that every additional insulation layer (e.g., contamination, paint, veneer) noticeably weakens the grip. Magnetic products operate optimally during direct contact; air break kills the power. Observe how flashily the load capacity fall, when the magnet does not touch tightly to the metal substrate. When planning the assembly, eliminate additional spacers.

Table 2: Slippage load (vertical surface)
MP 25x7.5/4.5x5 / N38

Distance (mm)	Friction coefficient	Pull Force (kg/lbs/g/N)
0 mm	Stal (~0.2)	1.54 kg / 3.40 LBS 1544.0 g / 15.1 N
1 mm	Stal (~0.2)	1.41 kg / 3.11 LBS 1410.0 g / 13.8 N
2 mm	Stal (~0.2)	1.25 kg / 2.75 LBS 1248.0 g / 12.2 N
3 mm	Stal (~0.2)	1.07 kg / 2.37 LBS 1074.0 g / 10.5 N
5 mm	Stal (~0.2)	0.74 kg / 1.64 LBS 744.0 g / 7.3 N
10 mm	Stal (~0.2)	0.24 kg / 0.53 LBS 240.0 g / 2.4 N
15 mm	Stal (~0.2)	0.07 kg / 0.16 LBS 74.0 g / 0.7 N
20 mm	Stal (~0.2)	0.02 kg / 0.05 LBS 24.0 g / 0.2 N
30 mm	Stal (~0.2)	0.00 kg / 0.01 LBS 4.0 g / 0.0 N
50 mm	Stal (~0.2)	0.00 kg / 0.00 LBS 0.0 g / 0.0 N

The following data indicates the theoretical weight limit sufficient to initiate the shifting of the magnet down against a upright metal surface (assuming standard friction coefficient). This value varies with the gap size between the magnet and the surface.

Table 3: Vertical assembly (shearing) - vertical pull
MP 25x7.5/4.5x5 / N38

Surface type	Friction coefficient / % Mocy	Max load (kg/lbs/g/N)
Raw steel	µ = 0.3 30% Nominalnej Siły	2.32 kg / 5.11 LBS 2316.0 g / 22.7 N
Painted steel (standard)	µ = 0.2 20% Nominalnej Siły	1.54 kg / 3.40 LBS 1544.0 g / 15.1 N
Oily/slippery steel	µ = 0.1 10% Nominalnej Siły	0.77 kg / 1.70 LBS 772.0 g / 7.6 N
Magnet with anti-slip rubber	µ = 0.5 50% Nominalnej Siły	3.86 kg / 8.51 LBS 3860.0 g / 37.9 N

When mounting a magnet on a upright plane (e.g., a car body), it you can count on only about 1/5 of its nominal power. Gravitational force and a low friction coefficient influence the fact that holders move down easier than they pop off the substrate. Want to create a wall mount? Remember that the sliding force is much weaker than the perpendicular breakaway force. On a painted metal, the element will slide down under a much lighter cargo. Application of an anti-slip layer can drastically improve the result.

Table 4: Steel thickness (substrate influence) - sheet metal selection
MP 25x7.5/4.5x5 / N38

Steel thickness (mm)	% power	Real pull force (kg/lbs/g/N)
0.5 mm	10%	0.77 kg / 1.70 LBS 772.0 g / 7.6 N
1 mm	25%	1.93 kg / 4.25 LBS 1930.0 g / 18.9 N
2 mm	50%	3.86 kg / 8.51 LBS 3860.0 g / 37.9 N
3 mm	75%	5.79 kg / 12.76 LBS 5790.0 g / 56.8 N
5 mm	100%	7.72 kg / 17.02 LBS 7720.0 g / 75.7 N
10 mm	100%	7.72 kg / 17.02 LBS 7720.0 g / 75.7 N
11 mm	100%	7.72 kg / 17.02 LBS 7720.0 g / 75.7 N
12 mm	100%	7.72 kg / 17.02 LBS 7720.0 g / 75.7 N

A thin metal plate is unable to focus the full magnetic flux, which squanders power of the holder. If you install a neodymium to a thin surface, the magnetism will penetrate right through and the holding will be smaller. To utilize 100% of this magnet's power, you require a sufficiently solid element of steel. The saturation effect means that on delicate walls (e.g., car bodies), the magnet shows lower pull force. We suggest choosing the steel cross-section from these parameters.

Table 5: Thermal stability (stability) - power drop
MP 25x7.5/4.5x5 / N38

Ambient temp. (°C)	Power loss	Remaining pull (kg/lbs/g/N)	Status
20 °C	0.0%	7.72 kg / 17.02 LBS 7720.0 g / 75.7 N	OK
40 °C	-2.2%	7.55 kg / 16.65 LBS 7550.2 g / 74.1 N	OK
60 °C	-4.4%	7.38 kg / 16.27 LBS 7380.3 g / 72.4 N
80 °C	-6.6%	7.21 kg / 15.90 LBS 7210.5 g / 70.7 N
100 °C	-28.8%	5.50 kg / 12.12 LBS 5496.6 g / 53.9 N

Classic neodymiums irreversibly lose parameters past the thermal threshold. Protect against heat – high temperature can irreversibly damage this magnet. As the temperature rises, the neodymium's force temporarily decreases. Refrain from using this magnet close to heaters exceeding its safe range. Exceeding the critical threshold will lead to irreversible degradation of magnetic properties.

*Important note: Heat tolerance depends not only on the material grade, but also on the magnet's shape. Low-profile magnets (low Pc) risk losing magnetic properties sooner compared to rod magnets. The danger warning in the table signals a risk of irreversible loss for this specific geometry.

Table 6: Two magnets (repulsion) - field range
MP 25x7.5/4.5x5 / N38

Gap (mm)	Attraction (kg/lbs) (N-S)	Shear Strength (kg/lbs/g/N)	Repulsion (kg/lbs) (N-N)
0 mm	9.91 kg / 21.84 LBS 3 484 Gs	1.49 kg / 3.28 LBS 1486 g / 14.6 N	N/A
1 mm	9.51 kg / 20.96 LBS 3 909 Gs	1.43 kg / 3.14 LBS 1426 g / 14.0 N	8.56 kg / 18.87 LBS ~0 Gs
2 mm	9.05 kg / 19.94 LBS 3 813 Gs	1.36 kg / 2.99 LBS 1357 g / 13.3 N	8.14 kg / 17.95 LBS ~0 Gs
3 mm	8.54 kg / 18.83 LBS 3 705 Gs	1.28 kg / 2.82 LBS 1281 g / 12.6 N	7.69 kg / 16.94 LBS ~0 Gs
5 mm	7.45 kg / 16.42 LBS 3 460 Gs	1.12 kg / 2.46 LBS 1117 g / 11.0 N	6.70 kg / 14.78 LBS ~0 Gs
10 mm	4.78 kg / 10.53 LBS 2 771 Gs	0.72 kg / 1.58 LBS 717 g / 7.0 N	4.30 kg / 9.48 LBS ~0 Gs
20 mm	1.54 kg / 3.41 LBS 1 576 Gs	0.23 kg / 0.51 LBS 232 g / 2.3 N	1.39 kg / 3.06 LBS ~0 Gs
50 mm	0.06 kg / 0.13 LBS 312 Gs	0.01 kg / 0.02 LBS 9 g / 0.1 N	0.05 kg / 0.12 LBS ~0 Gs
60 mm	0.03 kg / 0.06 LBS 202 Gs	0.00 kg / 0.01 LBS 4 g / 0.0 N	0.02 kg / 0.05 LBS ~0 Gs
70 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
80 mm	0.01 kg / 0.01 LBS 97 Gs	0.00 kg / 0.00 LBS 1 g / 0.0 N	0.00 kg / 0.00 LBS ~0 Gs
90 mm	0.00 kg / 0.01 LBS 71 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 54 Gs	0.00 kg / 0.00 LBS 0 g / 0.0 N	0.00 kg / 0.00 LBS ~0 Gs

Two magnets attract each other from a wider radius than a magnet and steel combination. The connection of two magnets generates a stronger field and a larger range of performance. Planning to create a strong closure? Apply two magnets instead of a neodymium and a steel. Be careful that when bringing together two magnets, the collision energy is huge. The levitation is marginally weaker than the attraction, but still impressive.
*Field value for N-N configuration drops to ~0 Gs at the geometric center of the gap (caused by magnetic field nullification).
Note: Results apply to friction force of a pair of same neodymium magnets (friction coefficient ~0.15 for Ni-Ni layer).

Table 7: Safety (HSE) (electronics) - precautionary measures
MP 25x7.5/4.5x5 / N38

Object / Device	Limit (Gauss) / mT	Safe distance
Pacemaker	5 Gs (0.5 mT)	9.5 cm
Hearing aid	10 Gs (1.0 mT)	7.5 cm
Timepiece	20 Gs (2.0 mT)	6.0 cm
Mobile device	40 Gs (4.0 mT)	4.5 cm
Remote	50 Gs (5.0 mT)	4.0 cm
Payment card	400 Gs (40.0 mT)	2.0 cm
HDD hard drive	600 Gs (60.0 mT)	1.5 cm

Powerful magnet radiation is a large risk to electronics and medical implants. These neodymiums generate a field that destroys function of digital equipment. Be aware: the invisible magnetic field passes through tissues and glass. Increased vigilance must be taken by people with cochlear implants and insulin pumps. The risk also applies to: automatic timepieces, remotes, speakers, and screens. Avoid contact with magnetic cards, hard drives, or sensitive navigation tools.

Table 8: Collisions (kinetic energy) - collision effects
MP 25x7.5/4.5x5 / N38

Start from (mm)	Speed (km/h)	Energy (J)
10 mm	22.95 km/h (6.38 m/s)	0.36 J
30 mm	36.43 km/h (10.12 m/s)	0.91 J
50 mm	46.96 km/h (13.04 m/s)	1.52 J
100 mm	66.40 km/h (18.44 m/s)	3.03 J

NdFeB products are very brittle – a violent impact against metal causes immediate chipping. Watch the impact speed – a neodymium left loose speeds with massive force. Kinetic force can cause material chips or painful pinches to fingers. Always hold the magnet during bringing near metal so it doesn't hit violently against the metal. A contact at a velocity of dozens of km/h ends with a crack of the magnet. Use safety goggles when playing with large magnets.

Table 9: Anti-corrosion coating durability
MP 25x7.5/4.5x5 / 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)

The SST (salt spray test) is an industry standard for determining coating lifespan in harsh conditions. Improper coating selection is the most common cause of magnet failure over time.

Table 10: Construction data (P_c)
MP 25x7.5/4.5x5 / N38

Parameter	Value	SI Unit / Description
Magnetic Flux	9 759 Mx	97.6 µWb
P_c Coefficient	0.25	Low (Flat)

Flux value emitted by the magnet pole. Key data when building generators as well as sensors. P_c value defines the working geometry.

Table 11: Submerged application
MP 25x7.5/4.5x5 / N38

Environment	Effective steel pull	Effect
Air (land)	7.72 kg	Standard
Water (riverbed)	8.84 kg (+1.12 kg buoyancy gain)	+14.5%

Rust risk: This magnet has a standard nickel coating. After use in water, it must be dried and maintained immediately, otherwise it will rust!

Contrary to myths, water does not block the magnetic field. However, remember the water resistance when pulling the rope quickly.

1. Wall mount (shear)

*Warning: On a vertical wall, the magnet holds merely ~20% of its max power.

2. Plate thickness effect

*Thin metal sheet (e.g. computer case) significantly weakens the holding force.

3. Power loss vs temp

*For N38 grade, the critical limit is 80°C.

4. Demagnetization curve and operating point (B-H)

chart generated for the permeance coefficient P_c (Permeance Coefficient) = 0.25

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 P_c (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 P_c 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%

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: 030194-2026

Measurement Calculator

Pulling force

Newtons (N)

Pounds (lbs)

Field Strength

Induction (Gs)

Induction (T)

Insert a value into any field, and the remaining fields change automatically.

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It is ideally suited for places where solid attachment of the magnet to the substrate is required without the risk of detachment. Thanks to the hole (often for a screw), this model enables quick installation to wood, wall, plastic, or metal. This product with a force of 7.72 kg works great as a cabinet closure, speaker holder, or mounting element in devices.

This material behaves more like porcelain than steel, so it doesn't forgive mistakes during mounting. One turn too many can destroy the magnet, so do it slowly. The flat screw head should evenly press the magnet. Remember: cracking during assembly results from material properties, not a product defect.

Moisture can penetrate micro-cracks in the coating and cause oxidation of the magnet. Damage to the protective layer during assembly is the most common cause of rusting. This product is dedicated for indoor use. For outdoor applications, we recommend choosing rubberized holders or additional protection with varnish.

The inner hole diameter determines the maximum size of the mounting element. For magnets with a straight hole, a conical head can act like a wedge and burst the magnet. Always check that the screw head is not larger than the outer diameter of the magnet (25 mm), so it doesn't protrude beyond the outline.

This model is characterized by dimensions Ø25x5 mm and a weight of 17.81 g. The pulling force of this model is an impressive 7.72 kg, which translates to 75.69 N in newtons. The mounting hole diameter is precisely 7.5/4.5 mm.

These magnets are magnetized axially (through the thickness), which means one flat side is the N pole and the other is S. If you want two such magnets screwed with cones facing each other (faces) to attract, you must connect them with opposite poles (N to S). We do not offer paired sets with marked poles in this category, but they are easy to match manually.

Strengths as well as weaknesses of rare earth magnets.

Pros

Apart from their consistent magnetic energy, neodymium magnets have these key benefits:

They retain magnetic properties for nearly ten years – the loss is just ~1% (in theory),
Magnets perfectly resist against loss of magnetization caused by foreign field sources,
Thanks to the elegant finish, the surface of Ni-Cu-Ni, gold-plated, or silver-plated gives an elegant appearance,
Neodymium magnets deliver maximum magnetic induction on a small area, which increases force concentration,
Due to their durability and thermal resistance, neodymium magnets can operate (depending on the shape) even at high temperatures reaching 230°C or more...
Considering the option of flexible forming and adaptation to individualized requirements, neodymium magnets can be manufactured in a variety of geometric configurations, which expands the range of possible applications,
Versatile presence in electronics industry – they are commonly used in computer drives, drive modules, medical devices, also modern systems.
Compactness – despite small sizes they provide effective action, making them ideal for precision applications

Cons

Characteristics of disadvantages of neodymium magnets and proposals for their use:

To avoid cracks under impact, we suggest using special steel holders. Such a solution secures the magnet and simultaneously improves its durability.
Neodymium magnets demagnetize when exposed to high temperatures. After reaching 80°C, many of them experience permanent drop of power (a factor is the shape as well as dimensions of the magnet). We offer magnets specially adapted to work at temperatures up to 230°C marked [AH], which are very resistant to heat
They rust in a humid environment. For use outdoors we advise using waterproof magnets e.g. in rubber, plastic
Limited possibility of creating threads in the magnet and complex forms - recommended is a housing - magnetic holder.
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 small components of these devices are able to complicate diagnosis medical when they are in the body.
Higher cost of purchase is one of the disadvantages compared to ceramic magnets, especially in budget applications

Lifting parameters

Best holding force of the magnet in ideal parameters – what affects it?

Breakaway force is the result of a measurement for the most favorable conditions, including:

on a plate made of structural steel, perfectly concentrating the magnetic flux
whose thickness equals approx. 10 mm
with an polished contact surface
without any clearance between the magnet and steel
during pulling in a direction vertical to the plane
at standard ambient temperature

Magnet lifting force in use – key factors

Bear in mind that the working load may be lower subject to elements below, starting with the most relevant:

Clearance – the presence of foreign body (rust, dirt, air) acts as an insulator, which lowers capacity steeply (even by 50% at 0.5 mm).
Angle of force application – maximum parameter is reached only during perpendicular pulling. The force required to slide of the magnet along the surface is typically several times lower (approx. 1/5 of the lifting capacity).
Plate thickness – too thin plate does not close the flux, causing part of the flux to be escaped to the other side.
Steel type – mild steel gives the best results. Alloy steels decrease magnetic properties and lifting capacity.
Surface condition – ground elements ensure maximum contact, which increases force. Uneven metal reduce efficiency.
Thermal factor – high temperature weakens magnetic field. Exceeding the limit temperature can permanently damage the magnet.

Lifting capacity was assessed by applying a smooth steel plate of suitable thickness (min. 20 mm), under vertically applied force, in contrast under parallel forces the lifting capacity is smaller. In addition, even a slight gap between the magnet’s surface and the plate decreases the load capacity.

H&S for magnets

No play value

Only for adults. Tiny parts pose a choking risk, leading to intestinal necrosis. Keep out of reach of kids and pets.

Machining danger

Mechanical processing of neodymium magnets carries a risk of fire hazard. Magnetic powder reacts violently with oxygen and is difficult to extinguish.

Handling guide

Handle magnets consciously. Their huge power can shock even professionals. Plan your moves and do not underestimate their power.

Protect data

Equipment safety: Strong magnets can damage data carriers and delicate electronics (heart implants, medical aids, mechanical watches).

Crushing force

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

Sensitization to coating

Warning for allergy sufferers: The Ni-Cu-Ni coating consists of nickel. If skin irritation happens, immediately stop working with magnets and use protective gear.

Operating temperature

Keep cool. NdFeB magnets are sensitive to heat. If you need operation above 80°C, ask us about special high-temperature series (H, SH, UH).

GPS Danger

Be aware: rare earth magnets produce a field that interferes with sensitive sensors. Maintain a separation from your mobile, tablet, and GPS.

Implant safety

For implant holders: Strong magnetic fields affect electronics. Maintain at least 30 cm distance or ask another person to work with the magnets.

Eye protection

Despite metallic appearance, the material is delicate and cannot withstand shocks. Do not hit, as the magnet may shatter into hazardous fragments.

Caution! Want to know more? Check our post: Why are neodymium magnets dangerous?

MP 25x7.5/4.5x5 / N38 - ring magnet

Technical of the product - MP 25x7.5/4.5x5 / N38 - ring magnet

Magnetic properties of material N38

Physical properties of sintered neodymium magnets Nd2Fe14B at 20°C

Physical analysis of the assembly - data

Table 1: Static pull force (force vs gap) - power drop MP 25x7.5/4.5x5 / N38

Table 2: Slippage load (vertical surface) MP 25x7.5/4.5x5 / N38

Table 3: Vertical assembly (shearing) - vertical pull MP 25x7.5/4.5x5 / N38

Table 4: Steel thickness (substrate influence) - sheet metal selection MP 25x7.5/4.5x5 / N38

Table 5: Thermal stability (stability) - power drop MP 25x7.5/4.5x5 / N38

Table 6: Two magnets (repulsion) - field range MP 25x7.5/4.5x5 / N38

Table 7: Safety (HSE) (electronics) - precautionary measures MP 25x7.5/4.5x5 / N38

Table 8: Collisions (kinetic energy) - collision effects MP 25x7.5/4.5x5 / N38

Table 9: Anti-corrosion coating durability MP 25x7.5/4.5x5 / N38

Table 10: Construction data (Pc) MP 25x7.5/4.5x5 / N38

Table 11: Submerged application MP 25x7.5/4.5x5 / N38

1. Wall mount (shear)

2. Plate thickness effect

3. Power loss vs temp

4. Demagnetization curve and operating point (B-H)

Material specification

Environmental data

Pulling force

Field Strength

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MPL 45x25x10 / N38 - lamellar magnet

Strengths as well as weaknesses of rare earth magnets.

Pros

Cons

Lifting parameters

Best holding force of the magnet in ideal parameters – what affects it?

Magnet lifting force in use – key factors

H&S for magnets

No play value

Machining danger

Handling guide

Protect data

Crushing force

Sensitization to coating

Operating temperature

GPS Danger

Implant safety

Eye protection

Physical properties of sintered neodymium magnets Nd₂Fe₁₄B at 20°C

Table 1: Static pull force (force vs gap) - power drop
MP 25x7.5/4.5x5 / N38

Table 2: Slippage load (vertical surface)
MP 25x7.5/4.5x5 / N38

Table 3: Vertical assembly (shearing) - vertical pull
MP 25x7.5/4.5x5 / N38

Table 4: Steel thickness (substrate influence) - sheet metal selection
MP 25x7.5/4.5x5 / N38

Table 5: Thermal stability (stability) - power drop
MP 25x7.5/4.5x5 / N38

Table 6: Two magnets (repulsion) - field range
MP 25x7.5/4.5x5 / N38

Table 7: Safety (HSE) (electronics) - precautionary measures
MP 25x7.5/4.5x5 / N38

Table 8: Collisions (kinetic energy) - collision effects
MP 25x7.5/4.5x5 / N38

Table 9: Anti-corrosion coating durability
MP 25x7.5/4.5x5 / N38

Table 10: Construction data (P_c)
MP 25x7.5/4.5x5 / N38

Table 11: Submerged application
MP 25x7.5/4.5x5 / N38