Ferrite (ceramic) magnets are made from iron oxide with strontium or barium. They contain no rare earths [1], so they are not affected by rare earth export rules or by the price swings of neodymium, dysprosium and terbium. They are cheap [1], corrosion-resistant without a coating [1], and work up to about 250°C.
The trade-off
Ferrite gives the least force per volume, so a ferrite part is larger than a neodymium part doing the same job. It also becomes more vulnerable to demagnetization in the cold rather than in the heat, which matters for outdoor and refrigeration uses.
Where it often wins
Wherever there is room for a larger magnet and cost matters: speakers, small DC motors and fans, holding and fastening, magnetic separators, sensors and signage. Flexible magnets (sheets, rolls and strips) are also ferrite-based, which is why their prices are far steadier than those of neodymium.
A quick test before switching
Check four things: the force you need, the space you have, the working temperature including the cold end, and whether the design can change. If the force target is modest and there is room, ferrite is usually the lowest-risk and lowest-cost option. If space is tight, stay with neodymium and manage the grade and the supply as described in our other articles.
We supply ferrite blocks, discs, rings and arcs as well as flexible magnet sheets, rolls and strips. Tell us the job the magnet has to do and we will say whether ferrite can handle it.
References
[1] Wikipedia contributors. Ferrite (magnet). Wikipedia, The Free Encyclopedia. https://en.wikipedia.org/wiki/Ferrite_(magnet)