Proficiency testing for the thermal sensitivity of pentaerythritol tetranitrate (PETN) and cyclotrimethylenetrinitramine (RDX) utilizing Differential Scanning Calorimetry (DSC)

Abstract

Differential Scanning Calorimetry (DSC) is a method of testing the thermal sensitivity of energetic materials. DSC is the most commonly used thermal analysis technique due to its ease of operation and rapid analysis. Furthermore, it provides precise, reproducible heat flow measurements.1 Thermal sensitivity testing determines the potential hazards of energetic materials when exposed to increasing levels of heat. Heat capacity measurements are particularly relevant when mixing, drying, transferring, and/or storing energetic materials.1 Two of the most commonly used explosives are PETN and RDX. PETN, or pentaerythritol tetranitrate, is a high explosive that is used in military detonating cord and blasting caps.2 RDX, or cyclotrimethylenetrinitramine, is used extensively in military munitions.3 As a means to increase the validity of thermal sensitivity testing, proficiency tests can be performed to improve protocols and standardization. The Explosive Testing Users Group, organized by Safety Management Services, Inc., developed a Round Robin testing project, and selected thermal analysis of PETN and RDX. For this research, a TA Instruments, Inc. SDT 650 was used to test the thermal sensitivity of the explosive standards. This work demonstrates the DSC proficiency testing performed at the CENFEX Fire and Explosives Research Laboratory. Results from the laboratory were compared to federal, national, and international laboratories participating in the Round Robin testing project. Statistical analyses demonstrated similarities among participating laboratories and identified potential protocol and standardization improvements.