Burning of antimony/potassium permanganate pyrotechnic compositions in closed systems

✍ Scribed by Michael W. Beck; Michael E. Brown

• Book ID: 103038268
• Publisher: Elsevier Science
• Year: 1986
• Tongue: English
• Weight: 599 KB
• Volume: 65
• Category: Article
• ISSN: 0010-2180
• DOI: 10.1016/0010-2180(86)90040-4

✦ Synopsis

The antimony/potassium permanganate pyrotechnic system is not gasless although it is used in sealed electric delay detonators. Burning rates of identical compositions vary according to the extent to which the system is confined. The variation is especially marked for the high fuel compositions which are the less gassy. Pressure profiles and burning rates have been measured in simulated detonators, with and without venting. For high fuel compositions, sealing the system increases the burning rate considerably. When the proportion of fuel is lower, the effect is not as great. The low fuel compositions form a solid product slag which tends to seal the column and force the hot oxygen gas evolved during decomposition of the KMnO4 forward. The unburned powder is thus brought more rapidly to its ignition temperature (-500°C) and the burning rate is increased. The high fuel compositions give a molten product and thus the ignition chamber must be sealed to ensure forward movement of hot gas.