Ignition system
An ignition system includes a multi-metallic ignition body that has at least two metallic elements in contact with each other. The metallic elements define an ignition initiation temperature above which there is a self-sustaining alloying reaction. A fluorine-containing body is in contact with the multi-metallic ignition body. The metallic elements may include palladium or palladium-ruthenium and aluminum.
1. An ignition system comprising:
a pyrotechnic wire having an outer jacket encasing an inner core, the outer jacket including palladium and ruthenium, and the inner core including aluminum, the pyrotechnic wire igniting above an ignition temperature in an alloying reaction producing a thermal release; and
an oxidizer augmenting the thermal release by exothermic reaction with at least one of the palladium, the ruthenium, the aluminum, or reaction products thereof, wherein the oxidizer is a fluorine-containing polymer coating in contact with an outer surface of the outer jacket and encasing the pyrotechnic wire and the coating also protects the wire from moisture infiltration.
2. The ignition system as recited in claim 1 , wherein the fluorine-containing polymer coating includes a fluorocarbon polymer with carbon-fluorine bonds.
3. The ignition system as recited in claim 1 , wherein the fluorine-containing polymer coating is selected from a group consisting of polytetrafluoroethylene (PTFE), fluorinated ethylene propylene (FEP), polyvinylidene fluoride (PVF), hexafluoropropylene (HFP), polyvinylfluoride (PVD), polyethylenetetrafluoroethylene (ETFE), and combinations thereof.
4. The ignition system as recited in claim 1 , wherein the outer jacket has, by weight, approximately 95% of palladium and approximately 5% of ruthenium.
5. The ignition system as recited in claim 1 , wherein the inner core has, by weight, approximately 95% of aluminum.
6. The ignition system as recited in claim 1 , wherein the coating is of uniform thickness.
7. The ignition system as recited in claim 1 , wherein the coating is an outermost layer and has an exposed outer surface.