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For the development of an Exploding Foil Initiator for Insensitive Munitions applications the following topics are of
interest: the electrical circuit, the exploding foil, the velocity of the flyer, the driver explosive, the secondary flyer and
the acceptor explosive. Several parameters of the EFI have influences on the velocity of the flyer. To investigate these
parameters a Fabry-Perot Velocity Interferometer System (F-PVIS) has been used. The light to and from the flyer is
transported by a multimode fibre terminated with a GRIN-lens. By this method the velocity of very tiny objects (0.1
mm), can be measured. The velocity of flyer can be recorded with nanosecond resolution, depending on the Fabry-Perot
etalon and the streak camera. With this equipment the influence of the dimensions of the exploding foil and the flyer on
the velocity and the acceleration of the flyer are investigated. Also the integrity of the flyer during flight can be analyzed.
To characterize the explosive material, to be used as driver explosive in EFI's, the initiation behaviour of the explosive
has been investigated by taking pictures of the explosion with a high speed framing and streak camera. From these
pictures the initiation distance and the detonation behaviour of the explosive has been analyzed. Normally, the driver
explosive initiates the acceptor explosive (booster) by direct contact. This booster explosive is embedded in the main
charge of the munitions. The combination of initiator, booster explosive and main charge explosive is called the
detonation train. In this research the possibility of initiation of the booster by an intermediate flyer is investigated. This
secondary flyer can be made of different materials, like aluminium, steel and polyester with different sizes. With the aid
of the F-PVIS the acceleration of the secondary flyer is investigated. This reveals the influence of the thickness and
density of the flyer on the acceleration and final velocity. Under certain circumstances the flyer breaks up in several parts
and several velocities at the same time have been recorded. Several flyer materials and dimensions exist that are able to
initiate very insensitive explosives like TATB.
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