Neodymium Magnet Surface Gauss vs Pull Force: Which Result Should You Specify?
A neodymium magnet quotation may include a surface field in gauss, a pull force, or both. These results answer different questions. Before comparing suppliers, decide which measured result relates to your product and define the conditions under which it will be checked.
This guide helps buyers prepare a magnetic acceptance requirement. Start with the function of the finished assembly, then agree the measurement method and limits with the supplier and the responsible product engineer.
What does a surface gauss value describe?
Gauss is a unit of magnetic flux density. A field measurement describes the field at a defined location, with a defined probe orientation. It is not a force reading. A catalogue's surface value may also be calculated, so ask whether a quoted value is calculated, typical or an agreed inspection limit.
For a sensing application, identify the location where the field matters to the device. A reading at the magnet face is not automatically the field at a sensor positioned farther away. Record the relevant axis and distance on the inquiry drawing.
What does a pull-force result describe?
A pull test measures the force needed to separate a magnet from a specified counterpart under the test arrangement. The steel target or second magnet, separation, contact condition and direction of pulling affect the result. A value measured against a flat steel plate should therefore be compared with results obtained under the same conditions.
For a holding or closure application, describe the actual counterpart and the intended movement. Ask the product team whether a component pull test, an assembly opening test or another agreed check best represents the requirement.
Can one result replace the other?
A single gauss reading does not uniquely define a magnet's pull force. Shape and the surrounding magnetic circuit matter, so two parts should not be ranked for an assembly only by whichever has the higher surface field. Likewise, a strong pull result does not establish the field at a chosen sensor position.
If both results are needed, define two requirements with their own methods. Avoid a generic request for 'high magnetic strength' when the supplier needs to know which characteristic will be used to accept the delivered parts.
Make the measurement repeatable
For a field check, agree the instrument and probe reference, measurement position, orientation and fixture. The active sensing area can be recessed inside a Hall probe, so touching the probe body to a magnet does not by itself define the sensing distance. Record the relevant temperature conditions where required.
For a pull check, describe the target, gap, fixture, pulling direction and agreed procedure. State the units, sampling plan and acceptance limits for each check. Keep those details with the sample approval so production and receiving teams can use a comparable method.
What to send with your inquiry
Send XILAI the magnet drawing, intended assembly, relevant working gap and the result you need to verify. Include any existing test method, sample report or acceptance limits. Where the method is still open, identify that early so the project team can agree a useful check before a production order is released.