Fluorosilicone rubber sheets are available to MIL-R-25988 as well as other fluid resistant specifications. They are not recommended for exposure to brake fluids, hydrazine, or ketones.
The material has better fuel and oil resistance than other silicone elastomers but maintains silicone’s high temperature advantage. Featuring good compression set and resilience properties, fluorosilicone compounds are suitable for exposure to air, sunlight, ozone, chlorinated and aromatic hydrocarbons.
In applications where contact with jet fuel, solvents, gasoline, or crude oil is required, this elastomer is serviceable over a temperature range of -60°C to 177°C (-76°F to 350°F). In dry heat, the serviceable temperature range is extended up to 232°C (450°F).
Physical properties—including tensile strength, elongation, and tear resistance—are comparable to those of general purpose silicone rubber compounds.
Fluorosilicone is used in applications where normal silicone would degrade by harsh chemicals or fluids and is used where extreme conditions exist. Fluorosilicone is most often used in aerospace applications for systems requiring fuel and/or diester-based lubricant resistance up to 400°F. Although generally specified for aerospace use, due to its excellent fuel resistance and high temperature stability, Fluorosilicone is becoming an increasingly popular material for a broader range of sealing applications.
Due to limited physical strength, poor abrasion resistance, and high friction characteristics, Fluorosilicone elastomers are not generally recommended for dynamic sealing. They are predominately designed for static sealing use.
Some typical resistance values are listed below. Values for other fluids are available upon request.
|Immersion Medium||Immersion Conditions||Hardness Change, Points||Tensile Strength Change, %||Elongation Change, %||Volume Change, %|
|ASTM #1 oil||3 Days / 302ºF||-5||Nil||-5||Nil|
|ASTM Ref. Fuel B||3 Days / 302ºF||-20||-60||-35||30|
|SAE 10w-30w Motor Oil||30 Days / 350ºF||-9||-76||-80||3|
|Gasoline, Regular/Low Lead||24 Hrs / 77ºF||-12||-39||-30||21|
|Jet Fuel JP-4||3 Days / 350ºF||-25||-65||-20||25|
|Turbo Oil #35||3 Days / 302ºF||-10||-30||25||10|
|Mineral Spirits||30 Days / 75ºF||Nil||Nil||Nil||Nil|
|Trichloroethylene||5 Days / 120ºF||-10||Nil||Nil||20|
|Hydraulic Fluid, Type A||3 Days / 302ºF||-5||-10||-5||5|