SEO Title: N38M Sintered NdFeB Block Magnet 20x10x5 mm Ni-Cu-Ni Coated 100°C Rated
Meta Description: Sintered NdFeB block magnet, grade N38M, 20x10x5 mm, magnetized through thickness with ±0.1 mm tolerance and Ni-Cu-Ni coating. Max working temperature 100°C.
N38M Sintered NdFeB Block Magnet 20x10x5 mm Ni-Cu-Ni Coated
Grade N38M sintered NdFeB block, 20 × 10 × 5 mm, Ni-Cu-Ni coated and magnetized through the 5 mm thickness.
Product Summary
Sintered NdFeB block magnet in grade N38M, 20 × 10 × 5 mm, magnetized through the 5 mm thickness. Br above 1.23 T, Hcj above 1114 kA/m and a maximum working temperature of 100 °C keep magnetic output stable in compact drive and sensing assemblies. The standard Ni-Cu-Ni coating supports corrosion resistance, and Dy/Tb content below 0.1% keeps export documentation straightforward.
Key Features
N38M Grade Rated to 100 °C
Maximum working temperature of 100 °C suits appliance motors, encoders and equipment that runs continuously warm.
Energy Density of 287–310 kJ/m³
(BH)max in that range with Br above 1.23 T delivers usable holding force from a 20 × 10 × 5 mm footprint.
Square Loop for Stable Flux
Hcj above 1114 kA/m with Hk/Hcj above 95% supports consistent flux under normal working conditions.
±0.1 mm Tolerance, Through-Thickness Magnetization
Tight dimensions and magnetization through the 5 mm thickness simplify pick-and-place and automated assembly.
Ni-Cu-Ni Coating
Multilayer nickel-copper-nickel coating supports corrosion resistance and a long service life.
Dy/Tb Content Below 0.1%
Non-heavy rare earth formula is compliant with China export regulations and simplifies supply documentation.
Technical Specifications
Material
NdFeB (neodymium-iron-boron), sintered
Grade
N38M
Shape
Block
Dimensions
L 20 mm × W 10 mm × T 5 mm
Dimensional Tolerance
±0.1 mm
Magnetization Direction
Through thickness (5 mm)
Remanence Br
> 1.23 T
Coercivity Hcb
> 876 kA/m
Intrinsic Coercivity Hcj
> 1114 kA/m
Squareness Hk/Hcj
> 95%
Maximum Energy Product (BH)max
287–310 kJ/m³
Max Working Temperature
100 °C
Coating
Ni-Cu-Ni
Heavy Rare Earth Content
Dy/Tb below 0.1%
Models and Options
The standard configuration is the 38M block at 20 × 10 × 5 mm with through-thickness magnetization and Ni-Cu-Ni coating. Other dimension and grade combinations within the sintered NdFeB family are produced to customer drawings. Block, disc, ring, arc and trapezoid shapes are available, and zinc, nickel, epoxy or parylene coatings can be specified for different working environments.
Materials and Structure
The magnet is made from sintered NdFeB (neodymium-iron-boron) and finished as a dense block measuring 20 × 10 × 5 mm, magnetized through the 5 mm thickness. The surface carries a Ni-Cu-Ni multilayer coating. Production covers melting, hydrogen decrepitation, powder preparation, pressing, sintering, precision CNC machining, surface treatment and final magnetic testing, with full-lot traceability from raw material to finished product.
Applications
Brushless DC motors for household appliances
Encoders and position sensors
Office automation equipment such as printers and scanners
Small vibration motors for smart devices
Magnetic coupling assemblies
Automated door and window actuators
Customization
Beyond standard sizes, the technical team supports magnetic-circuit simulation, magnetic-field analysis and material selection, together with rapid prototyping and pilot-run trial production before serial manufacturing. Custom shapes, tolerances and coating systems are quoted from your drawing, required grade and annual volume.
FAQ
Which direction is this block magnetized?
It is magnetized through thickness, meaning through the 5 mm dimension of the 20 × 10 × 5 mm block.
What dimensional tolerance can I expect?
The stated tolerance for this block is ±0.1 mm, which supports precise assembly in automated lines.
What are the magnetic properties?
Br > 1.23 T, Hcb > 876 kA/m, Hcj > 1114 kA/m, Hk/Hcj > 95% and (BH)max between 287 and 310 kJ/m³.
Which coating is applied and why?
The standard coating is Ni-Cu-Ni, chosen for corrosion resistance and long service life. Salt-spray corrosion testing forms part of the in-house reliability testing programme.
Does the magnet contain heavy rare earths?
The stated formula keeps Dy/Tb content below 0.1%, which is compliant with China export regulations.
Can you supply other sizes, shapes or coatings?
Yes. Block, disc, ring, arc, trapezoid and customer-specific shapes are available, with zinc, nickel, epoxy or parylene coating options. Send your drawing and required grade for a review.
How is batch stability controlled?
Production runs through digital-intelligent workshops managed by ERP, MES and WMS systems for full-lot traceability, with rare-earth raw material inspection, in-process monitoring and magnetic property validation carried out in the in-house test centre.
To receive a quotation, please share grade, dimensions, coating, magnetization direction, tolerance requirements and estimated annual volume.
Image Filename and Alt Suggestions
Main image: 38m-ndfeb-block-magnet-20x10x5mm-ni-cu-ni-front.png — Alt: “N38M sintered NdFeB block magnet 20x10x5 mm with Ni-Cu-Ni coating viewed from the face”
Detail image (recommended): 38m-block-magnet-20x10x5mm-magnetization-through-thickness.png — Alt: “Close view of the N38M block showing magnetization through the 5 mm thickness”
Application image (recommended): ndfeb-block-magnet-grade-n38m-sensor-assembly.png — Alt: “Sintered NdFeB block magnet positioned for a position sensor assembly”
