Sensing the Thermal History of High-Explosive Detonations Using Thermoluminescent Microparticles

Thermoluminescent LiF:Mg, Ti (TLD-100) micro- particle sensors are demonstrated to record the thermal history of the environment around a high-explosive detonation. Microparticles are gamma-irradiated to fill their charge-carrier traps and then exposed to the detonation of 20 g of a plastic bonded HMX and Al explosive formulation at a test distance of approximately 22 cm from the center of the detonation. The thermal history of the microparticles is reconstructed by iteratively matching the degree of trap depopulation, derived from luminescence measurements, with that projected by theoretical simulations using appropriate models. Measurements and modeling indicate that the particles experienced a maximum temperature of 240 $^{\circ}{\rm C}$ , then cooled to 1 $^{\circ}{\rm C}$ above ambient temperature within 0.4 seconds. The resulting glow curve intensity is calculated to match the observed post-detonation signal to 3% averaged over the comparison values used for reconstruction.