Attached Printed Circuit Board Based Time-of-Arrival Measurements for Determining Detonation Velocities and Run-to-Detonation Distances

The detonation velocity is a key performance parameter for developing new energetic materials (EM). A common method uses short circuit pins in constant distances on the charge axis to detect the propagating detonation wave for deriving the velocity of detonation (VoD) from a fit of the time-dependent signal. This method is limited due to the diameter of the pins and the sensitivity of the sample since drilling holes is necessary to apply the method requiring large amounts of EM. At Fraunhofer ICT, we improved this technique using printed circuit boards (PCB) for a more precise spatial resolution which are attached to the outside of the charge for easier mounting. With this advanced method, the measurement length is scaled down by a factor of 50 and the amount of energetic material can be reduced by a factor of 10,000 without an effect on the charge itself. This enables the measurement of small charges, e.g. detonators. This paper gives an overview of the method itself and shows exemplary applications for determining detonation velocities with run distances in the hundreds of µm range and the determination of run-to-detonation distances in a simple experimental setup. Also, a discussion of possible future applications is given.