Octagonal shaped PTFE coated stirrer bars made using rare earth samarium-cobalt magnets, have greater magnetic strength than Alnico magnets.
- Totally resistant to demagnetisation
- Chemically inert
NB: The high magnetic coupling power of Sa-Co magnets can give rise to erratic stirring effects such as magnet migration and tumbling effect. The powerful attraction between the stirrer and the drive magnet system can give rise to the formation of PTFE particles caused by abrasion between stirrer magnet and the container base.