Experimental determination of ignition and combustion characteristics of insensitive gun propellants based on RDX and nitrocellulose

Safety improvements in the field of energetic materials led to the development of insensitive gun propellants. This article deals with ignition and combustion parameters of two commercial insensitive propellants, respectively based on RDX and nitrocellulose. Ignition is obtained thanks to a laser diode and ignition probabilities are given, along with ignition delays, overpressures and propagation rates. Experiments are performed under nitrogen and argon atmospheres, with initial pressures ranging between 10 and 70 bar and laser powers between 0.66 and 9.95 W. It is found that argon enhances combustion, especially on overpressures but not on ignition delays that are more sensitive to laser powers. Nitrocellulose-based propellants are found to be more reactive than RDX-based ones. Results on graphitized laboratory gun propellants based on the same materials are also given to discuss the results.