Ignition Growth Characteristics of JEOL Explosive during Cook-Off Tests

In order to study the reaction growth process of insensitive JEOL explosive after ignition under cook-off, a series of cook-off tests were carried out on JEOL explosive using a self-designed small cook-off bomb system. A thermocouple was used to measure the internal temperature of the explosive, and a camera recorded macro images of the cook-off process. The temperature change law of JEOL explosive before and after ignition under different heating rates and the smoke ejection caused by the reaction in the slit were studied. The research results showed that the ignition time decreased as the heating rate increased, while the ignition temperature was not sensitive to the heating rate. When the heating rate was faster, the internal temperature gradient of the explosive was larger, and the ignition point appeared at the highest temperature position. As the heating rate decreased, the internal temperature gradient of the explosive decreased, the ignition point appeared random, and multiple ignition points appeared at the same time. The growth process of the ignition point could be divided into severe thermal decomposition, slow combustion, and violent combustion stages. When the heating rate reduced from 7 to 1 °C/min, the burning rate obviously increased.