An Extension to the Critical Energy Criterion used to predict shock initiation thresholds

It has long been appreciated that the critical energy (Ec) criterion, developed by Walker and Wasley(1), has been limited in both the pressure range over which it applies(2), and in the number of explosive formulations which appear to obey it(3). The addition of a specific energy “cut‐off” to the criterion enables it to be applied to explosives previously considered to lie outside the original criterion, and to extend the range of impacts covered by the criterion in explosives which obey Ec within certain pressure limits. The new criterion appears particularly applicable to cast PBX formulations and insensitive high explosives such as TATB.