Experimental Research on Ignition and Burning of Heterogeneous Explosives under Drop-Weight Impact

In this work we presented an improved form of the drop-weight system in which, instead of being impacted directly by the drop weight, the sample was impacted by the upper anvil which was beforehand impacted by the drop weight.Based on this improved drop-weight system, the ignition and burning processes of HMX based plastic bonded explosives were recorded by a high-speed camera at the microsecond time scale.The experiment results indicate that, under low pressure and long pulse loading, heterogeneous explosives mainly undergo the process of compression→plastic flow→particle breaking→formation of local high temperature region→initiation→burning→quenching, which is a typical non-shock initiation process.But, because the explosive is heterogeneous at the mesoscale, the location of the high temperature region, the reaction duration and the reaction violence of heterogeneous explosive samples are different from each other under the same experimental conditions.