The main raw materials for AlNiCo-magnets are iron, aluminum (~9%), nickel (~13%) and cobalt (~24%). In addition, various other elements are added. Two different production techniques are used: the pouring technique and the sintering technique.
The following steps are used: Raw material assembly - mixing - melting - pouring - thermal treatment - testing - surface treatment - magnetization - final inspection. The finished magnet is very hard and can be further processed only by using diamond tools or the erosion process. AlNiCo- magnets are characterised by a high corrosion resistance. AlNiCo-magnets have an extremely low (negative) temperature coefficient and can be used at temperatures ranging from -250 to +500°C. Depending on the alloy, the remanence of AlNiCo-magnets lies between approximately 0.70 - 1.2 Tesla. The remanence is thus comparable to NdFeB-magnets. However, the coercive field strength of 50 - 150 kA/m is approximately 10 times smaller than that of NdFeB-magnets. AlNiCo-magnets are also available as plastic-bound magnets.
Chemical and magnetic characteristic data of cast AlNiCo-magnets