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We propose and demonstrate the use of polymethyl methacrylate (PMMA) for sensing elements based on the Faraday effect for the measurement of a pulsed high magnetic field generated by helical magnetic flux compression generators (HMCGs). The magneto-optic properties of sensing elements made with PMMA are investigated. The inherent linear birefringence is substantially suppressed by carefully annealing PMMA blocks. The Verdet constant of V = 3.251 rad T−1 m−1 and the normalized temperature dependence of VL (the product of the Verdet constant and the length of the sensing element) of −2.04 × 10−4 °C−1 are measured in the annealed PMMA material. The pulsed high magnetic field of up to ~27 kG is measured by the sensors made from annealed PMMA and the results are compared with those measured by inductive probes. They are in good agreement within ±1.5%. As an application, the annealed PMMA sensor is used in the measurement of a pulsed magnetic field generated by explosive-driven HMCGs.

The possibility of enhancing detonation properties by electric energy input was experimentally investigated. A piece of 2 mm thick sheet explosive was placed between two copper electrodes, and the electric energy, 5 kJ, was supplied to the detonating explosive from a capacitor bank. Energy deposited in the detonating explosive was estimated to be 3.2∼4.3 kJ. The detonation velocity was increased by 2.7∼3.2% on average and 8.2∼10.4% locally. This increase occurred with a time lag of 10∼18 μs after the electric energy input had started. It was speculated that the electric energy was supplied to the reaction zone in the form of heat, and that it took a short while for the heat energy to be transferred to the detonation front.

Detonation waves propagating in a cylindrical high explosive initiated peripherally at one end were photographed by using multislit steak technique. The slit plane consisted of several concentric circular slits and a linear one lying on the center of the circles. One of the interesting facts observed with this multislit configuration was that the detonation wave which appeared symmetric in linear slit streak might not be a circular one. And more details of the wave shapes were recorded in the streak of circular slit with smaller diameter.

Precise timing for x-ray bursts is crucial in acquiring useful information from flash radiographic experiments. Triggering the flash x-ray system near the muzzle is a difficult task because of the intrinsic nature of the muzzle blast. In this work a compact and reliable triggering method for near muzzle flash radiography is introduced; a piezoelectric pin probe attached at the end of the barrel. These types of probes have not been activated by the precursor shock wave, but they have been activated by the main blast wave only. Reliability in triggering the flash x-ray system has been confirmed throughout a series of flash radiographic experiments near the muzzle for gun barrels with calibers up to 105 mm.