Also referred to as fluoroelastomers, fluorocarbon compounds are thermoset elastomers containing fluorine. FKM makes excellent general purpose O-rings due to their exceptional resistance to chemicals, oil, and temperature extremes (-15° to +400° F). Specialty compounds can further extend the low temperature limit down to about -22° F for dynamic seals and about -40° F in static applications.
FKM usually has good compression set resistance, low gas permeability, and good resistance to ozone and sunlight. Over the last five decades, this remarkable combination of properties has prompted the use of FKM seals in a variety of demanding industries. Though they were initially formulated for use in aerospace applications, FKM compounds are now widely used in the automotive, appliance, fluid power, and chemical processing industries.