Duplex stainless steel contains a mixture of austenitic and ferritic grains within its microstructure. Austenitic microstructures are non-magnetic, but ferritic microstructures are. Therefore duplex grades are also considered magnetic.
Magnetic permeability is a measure of the attraction of a metal to a magnet. For austenitic stainless steels, such as Fermonic 50, the magnetic permeability is reported as <1.05. For duplex and super duplex stainless steels, the equivalent value would be around 50. For ferritic stainless steels, the magnetic permeability value may be in the hundreds. The difference between the duplex and ferritic value is not significant in normal circumstances – both can be considered as magnetic and can be handled and sorted by exploiting their magnetic properties.
If you have any more questions about our range of austenitic, duplex and super duplex stainless steels, please contact us today. A member of our team will be more than happy to help and can also advise you on the best option for your application.