SHOCK INITIATION THRESHOLDS FOR INSENSITIVE HIGH EXPLOSIVES

Work with conventional high explosives shows that the initiation thresholds for a variety of projectile types can be mapped onto a single curve. This curve is distinct from, although parallel to, the Pop Plot curve. In contrast for an insensitive high explosive, the location of the initiation thresholds appear divided between those forming a distinct threshold curve and those that appear to be a continuation of the Pop Plot. Projectile diameters larger than the failure diameter still form a distinct threshold, but smaller projectile diameters lie on the Pop Plot curve. Impacts lying on the threshold curve produce non‐divergent detonations which in many cases appear likely to remain non‐divergent or even fade. Those initial conditions that lie on the Pop Plot only need sufficient run distance in the explosive before a diverging detonation is achieved.