Characterization and evaluation of stability of defective charge under high overload

In order to quantitatively evaluate the overload stability of charge with defects, by adjusting the material and thickness of the waveform modulator, the waveform, amplitude, and pulse width of the loading signal were precisely controlled, based on the overload environmental force experimental device, the eigenvalues of charge load with different defects were measured, which can take into account the high overload pressure and wide pulse at the same time. The response degree of the charges under investigation was quantitatively characterized based on the burn marks, damage level, and mechanical fitting performance of the witness plates, grayscale numerical processing was applied to the surface images of the recovered witness plates after testing, the influence of the experimental system on the eigenvalues of charge load was quantified, and the correlation mechanism between charge response behavior and image grayscale was established. Based on clustering analysis, the primary stimulating factors affecting the stability of the charges, including defect diameter, flyer thickness, and the material and thickness of the waveform modulator, were classified, the corresponding conversion factors of the test device were introduced, the evaluation model of overload stability of defective charge was constructed, and the response critical pressure thresholds of different defective charges were predicted. The results indicate that the overload peak value greater than 1 GPa and high-impact pulse width greater than 100 μs can be achieved. With the increase of defect diameter, the response level of loading response increases significantly. The critical pressure of combustion reaction decreases from 0.71 GPa to 0.26 GPa with the increase of charge defect diameter from 0 mm to 12 mm. When the defect diameter of the charge reaches 10 mm, the critical pressure of deflagration reaction is 1.56 GPa. With the increase of defect diameter, the critical pressure of deflagration reaction decreases to 1.25 GPa when the defect is $\varnothing$12 mm. The critical reaction pressures predicted by the model are all within the confidence range of the experimental data surrounded by the minimum reaction overload pressure and the maximum unreacted overload pressure. The reliability of the model is verified, which verifies the reliability of the model.