Overview
How permanent magnets fit the application
Magnets make invisible fields observable in lessons on attraction, repulsion, induction, motors, sensing and materials. The most useful teaching magnet is one that makes the concept clear while remaining appropriate for the age group, supervision level and experimental setup.
Small neodymium magnets produce strong fields in compact demonstrations, but they can pinch, shatter and become ingestion hazards. Ceramic magnets are weaker and often easier to handle for introductory activities. Research and university projects may need higher grades or temperature-stable samarium cobalt when repeatable measurements matter.
Specify the system
Selection factors to define first
Learner age, supervision, pinch risk and ingestion risk
The field pattern or principle the activity is intended to demonstrate
Repeatability, measurement distance and required dimensional tolerance
Temperature, corrosion and impact exposure during repeated use
Material options
Magnet types commonly considered
These are starting points, not universal prescriptions. Temperature ratings and field performance depend on magnet geometry and the complete magnetic circuit.
Ceramic Grade 8
Visible, economical demonstrations where lower strength and larger size aid supervised handling.
Read the material guideN42 neodymium
Compact university experiments, sensors and prototypes with suitable handling controls.
Read the material guideSm2Co17 samarium cobalt
Temperature-dependent laboratory work and instruments that need stable field output.
Read the material guideGeometry
Useful shapes to compare
Stocked reference points
Representative magnets for evaluation
These individual sizes are useful physical reference points. Final selection should be checked against the required field, force, temperature and safety constraints.
Design and safety notes
- Strong magnets are not toys; keep them away from young children, implanted medical devices and magnetic media.
- Wear eye protection when brittle magnets could collide, chip or shatter, and use spacers for storage.
- For quantitative work, record the measurement distance and fixture orientation so results can be reproduced.