Magnetization direction definition

Diametrical Magnetization Explained

Direct answer: Diametrical magnetization runs across the diameter of a round disc, cylinder or ring, so the north and south poles are located on opposing curved sides. The term defines a direction, not the finished field strength or the identity of either physical pole. A controlled drawing must still name the datum, N/S side, viewing direction, part state and inspection path.

Prepared by Elite Magnets Application & Magnetization Engineering Team · Technical review by Elite Magnets Quality & Manufacturing Validation Team · Published 2026-09-12 · Updated 2026-09-01

Diametrical magnetization drawing card showing poles across a round part diameter — Engineering Evidence EM-DIAM-01 · ASSET-059 original direction-and-drawing card. The diagram defines references; it does not promise field output or fixture feasibility.

What diametrical magnetization means

Imagine a line passing through the center of a round magnet from one curved side to the opposite side. Diametrical magnetization uses that line as the primary direction. The two broad pole regions therefore appear across the side surface rather than on the two flat faces of an ordinary axially magnetized disc.

That definition applies to direction only. Material, dimensions, pole area, surrounding steel, air gap, temperature, magnetizing condition and the measurement setup still determine the useful magnetic result.

Round cylinder magnets whose shape alone does not identify magnetization direction — A disc or cylinder can be axial, diametrical or use another reviewed pattern. Shape is not a released pole specification.

Complete the direction on the drawing

Drawing field	What to define	Why it matters	Incomplete example
Physical datum	Named flat, slot, mark, key or angular feature	Links the magnetic direction to the manufactured part	“Across diameter” only
Polarity	Which referenced side is N and which is S	Prevents mirrored interpretation during assembly	Two unlabeled arrows
Viewing direction	The side from which the angular reference is read	Controls clockwise/counterclockwise meaning	Angle without a view
Part state	Loose, delivered, installed or fully assembled	The surrounding circuit can change the measured result	One value with no state
Inspection	Location, path, direction, fixture, method and limit	Makes the pole decision reproducible	“Check polarity”

The same reference must be understood by design, magnetization, assembly and final inspection.

CAD drawing review for a diametrically magnetized round component — Use a real geometry feature or controlled mark to remove the 180-degree ambiguity of a round part.

Where the direction can be useful

Diametrical orientation is often considered when a rotating part, side-facing sensor or lateral field path needs two opposing pole regions around the circumference. That is a screening reason, not a route approval. The final choice depends on the sensor position, air gap, steel circuit, required waveform or switching event, mechanical reference, assembly sequence and the feasible magnetization and inspection method.

If the design needs several alternating poles around a ring, the requirement is no longer described completely by “diametrical.” Pole count, sequence, pitch, start angle and scan path must be released as a multipole pattern.

Engineering test context for a rotating magnetic application — The useful direction is selected around the finished sensing, motion or coupling geometry and then verified in the defined state.

Do not confuse diametrical, axial and radial

Axial magnetization follows the part axis or thickness. Diametrical magnetization crosses a round part from one curved side to the other. Radial terminology is commonly used for inward/outward directions in ring geometry and needs its own pole and surface definition. For a direct option comparison, use the axial versus diametrical guide; for the broader specification framework, use magnetization direction and pole patterns.

Inputs for engineering and quotation review

Send the controlled drawing or model, diameter and length or thickness, material intent, physical angular datum, N/S orientation, delivery and assembly state, sensor or working position, air gap and surrounding steel, temperature and environment, quantity, and the proposed inspection characteristic. Review bonded NdFeB routes, Quality, and the existing RFQ form for project-specific review.

Frequently asked questions

Where are the poles on a diametrically magnetized cylinder?

They are on opposing curved sides across the diameter. The drawing must still identify which referenced side is north and which is south.

Can a disc magnet be diametrically magnetized?

It can be a design option, but shape alone does not approve material, geometry, fixture, field result or inspection feasibility.

Is diametrical magnetization stronger than axial magnetization?

Neither direction is universally stronger. Useful output depends on the complete material, geometry, circuit, gap, temperature and measurement condition.

Is diametrical the same as radial magnetization?

No. Diametrical crosses a round part from side to side; radial terminology uses an inward/outward reference and requires a separate pole definition.

What should a diametrical magnet drawing show?

Show the physical datum, N/S side, viewing direction, angular reference, delivery or assembly state, measurement path, method and acceptance criterion.

Source and evidence boundary

The dated Google SERP and directly read seller education page were used for terminology and question coverage. No competitor product value, field output, fixture, equipment or manufacturing capability was adopted.