MAGNETIC MATERIALS · MAGNETIC ASSEMBLIES · APPLICATION ENGINEERINGservices@china-empire.comWhatsApp +8613805876186
Engineering Resource

Magnet Design Guide

A drawing tells us what to make. The application tells us what the magnet has to survive and how it must perform.

Magnet Design Guide | Empire Magnets
Our review sequence

Application → magnetic solution

01

Application

Where is the magnet used? Motor, sensor, coupling, holding device, medical, energy or other system.

02

Environment

Operating / peak temperature, fluids, humidity, corrosion, shock and vibration.

03

Magnetic target

Flux density, force, torque, back-EMF, sensor threshold, field uniformity or air-gap target.

04

Geometry

Envelope, air gap, magnet dimensions, working point, mechanical retention and assembly constraints.

05

Material & grade

Compare NdFeB / SmCo / Ferrite / AlNiCo / Flexible, then choose grade/coercivity class.

06

Magnetization

Axial, diametric, radial, multipole, skewed or array orientation.

07

Protection & assembly

Coating, adhesive, sleeve, overmold, housing and handling requirements.

08

Validation

Magnetic, dimensional, environmental and assembly verification before mass production.

Temperature class is not enough by itself

Working point matters

A magnet in a closed magnetic circuit can tolerate heat differently from the same geometry in open circuit.

Geometry matters

Thin magnets and low permeance coefficients can be more vulnerable to irreversible demagnetization.

Test method matters

Surface field, total flux and BH-curve measurements answer different questions; the method should be agreed before acceptance.

Fixture matters

Customer and supplier tests should reproduce the same magnetic circuit or fixture when comparing high-temperature performance.

Quick selection

Material choice shortcuts

NeedFirst materials to evaluateEngineering note
Highest energy / smallest sizeNdFeBCheck temperature/coercivity and coating
High temperature + strong coercivitySmCoEvaluate 1:5 vs 2:17 and brittleness
Lowest cost at large volumeFerriteAccept larger magnet volume; grinding for tight dimensions
Very low temperature driftAlNiCoDesign the magnetic length/circuit to avoid self-demagnetization
Flexible sheet / strip / die-cutFlexible ferriteBinder/laminate controls temperature limit
Validated subsystemMagnetic assemblyReview mechanical retention, magnetization, balance, runout, flux and validation together

Send us these inputs

Drawing / CAD / BOM

PDF, STEP, DXF, Excel or BOM can be uploaded in the RFQ.

Operating conditions

Temperature, duty, environment, shock/vibration and expected service life.

Magnetic requirement

Flux, field, torque, force, back-EMF or functional pass/fail target.

Volume & timing

Prototype quantity, annual volume, sample target and SOP timing.

Inspection requirement

Critical dimensions, test method, sampling, PPAP/FAI or customer-specific documentation.

Confidentiality

NDA can be arranged before sensitive drawings or specifications are exchanged.

Magnet Design Guide engineering visual 1Magnet Design Guide engineering visual 2