Sintered samarium cobalt (SmCo) magnets, available since the early 1970's, offer the designer a tremendous combination of extremely high magnetic properties, outstanding thermal stability and excellent corrosion resistance. These characteristics make SmCo the ideal material in applications such as servo-motor, pump couplings, and sensors, particularly where the magnet is required to operate at high temperatures, across a broad temperature range or in a corrosive environment. The first alloy composition was SmCo5 with maximum energy products of about 18 MGOe (140 kJ/m3). Shortly after this development, an additional alloy composition, Sm2Co17 was developed. This was developed over time to provide over 30 MGOe (240 kJ/m3). Although processing of the 2-17 composition is more difficult, it also has the advantage of containing less Cobalt than the 1-5 composition. Raw material costs are lower. 2-17 is also very corrosion resistant and more stable at very high temperatures. Both types are manufactured by precision machining to satisfy specific customer needs.