| The initiation of explosives by laser-driven flyer has obvious advantages on improving the safety and initiation speed of initiators. When this technology is perfect, the interrelated products will be applied to the ammunitions, carrier rockets and other weapon systems instead of many active initiators. This replacement will improve the integrate capability of initiators. There have been many researches on shock initiation by laser-driven flyers, but many mechnisms of them were macroscopical and not systemic. In our work, the study of the initiation of explosives by laser-driven flyer was carried out both in experiment and in numerical simulation, which can provide theoretical and technical foundation for the application of this technology.Interactions between laser and metal films with and without confinements were researched. Using Boltzmann plot method we calculated the electron temperatures of copper and aluminum plasma, and the electron densities of the plasma were calculated by Saha-Eggert equation and the measured Stark broadening, both of whom were based on the laser-induced breakdown spectroscopy. The electron temperatures and densities of plasma generated with confinement were analyzed contrast to those without confinement. The results showed that the K9 substrate plays an important role in enhancing the electron temperatures and densities of metal plasma. As time evolved, the decreasing rate of plasma temperatures and densities with confinement was slower than those without confinement. When incident laser intensity increased, the rising rate of plasma temperatures and densities with confinement was quicker than those without confinement. Also, a model was presented that described the interaction of an ns-pulsed laser with metal target, as well as the resulting plume expansion and plasma formation. The plasma temperature and density calculated was in reasonable agreement with measured data from experiment.The influences of flyers'diameter, thickness, accelerating distance, composite flyers, and laser intensity on the velocity, the energy coupling coefficient and the impact stress of flyers were studied. The integrity of flyers was researched by impacting the PMMA. Also the characters of three composite flyers, which were CuO/Cu, CuO/Al and CuO/Al/Cu, were obtained. The results showed that flyers' velocity decreased with the rising of flyers'thickness, and increased with the rising of acceleration distance. As the laser energy absorbed and energetic layer, CuO/Al could improve the velocity of Al flyer by 10%. When the flyer's diameter and the acceleration distance rised, the flyer's energy coupling coefficient increased, but when laser intensity rised, the flyer's energy coupling coefficient began to decline.According to LSDW theory, a model was carried out to calculate the velocity of laser-driven flyer. The calculation results indicated that the flyer's velocity increased as the incident laser energy rised. By comparing the calculation results to the measured results, it was found that the calculation velocity of cooper showed a reasonable agreement with experiment, and the average error was 17.4%. The aluminum velocity calculated agree with that in the experiment well, the maximum difference of which was below 8%.Experiments of initiation of PETN and HNS by laser-driven flyer were carried out, and the criterion of P2τwas used to analyze the initiation. The shock initiation rules by flyers with different laser energy were received. Numerical simulation for the initiation of PETN by laser-driven flyer was carried out in AUTODYN code. The simulation results showed that both of Al flyer (velocity 4145 m·s-1) and Cu flyer (velocity 3389m·s-1) could initiated PETN successfully. The more thick of the flyer, the greater would be the pressure in the explosive if the flyers'velocity were same.
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