Machining and tolerances

Ceramic magnets are very hard and brittle, consequently machining must be done with a diamond wheel, and is easier when done prior to magnetization. Standard tolerances for ceramic magnet dimensions are +/-.005" for ground dimensions and +/- 2% of feature size for as sintered dimensions. Because of their brittleness these magnets will not withstand impact or flexing. We recommend that they not be used for structural purposes. Ceramic magnets are chemically inert non-conductors, which is a benefit in many applications. However, this feature does eliminate the use of the EDM process to produce samples or special shapes.

Common applications

• DC motors
• Magnetic separators
• MRI
• Automotive sensors
• Craft projects
• Refrigerator magnets

Temperature constraints and methods of magnetization

Maximum operating temperature for ceramic magnets is 250°C. Although you will experience magnetic losses when operating at elevated temperatures, the losses are recovered when the material is brought down to normal ambient temperature. However, operating in very cold temperatures (-20°C) can result in permanent losses of magnetic strength unless the circuit has been designed for such extremes. Magnetization: ceramic magnets must be magnetized in the direction of orientation, which is the same as the direction of pressing.

Added value services

Adams stocks a variant of square and rectangular blocks, discs and rings in ceramic 1,5 & 8 grades. Other configurations can be produced but are not stocked except for specific customer requirements. The standard sizes can be cut and ground to meet your specific requirements. We also produce stock and custom magnetic assemblies using ceramic magnets.

Download product specifications in PDF format.