IMX-101 is a high-performance insensitive high explosive composite mixture developed by BAE Systems and the United States Army to replace TNT in artillery shells.DTIC Background and Introduction to IMX-101, -102 and -103 The Application of New IM Explosive Candidates - DTIC Online IMX stands for "Insensitive Munitions eXplosives", which refers to the purpose of IMX-101: to provide explosive force equivalent to TNT without its sensitivity to shocks such as gunfire, explosions from improvised explosive devices, fire, and shrapnel. For example, the United States Army believes that a training incident in Nevada which killed seven Marines would not have occurred with the new explosive. On March 23, 2013, the United States Army ordered $780 million worth of the explosive, with a production of millions of pounds annually, to be produced by BAE at Holston Army Ammunition Plant in Tennessee. The new explosive will cost $8 per pound, compared to $6 per pound for TNT. As of 2023, IMX-101 filled shells are being used in the 2022 Russian invasion of Ukraine.
Time Magazine called IMX-101 one of the "50 best inventions of 2010".
Composition IMX-101 is composed of 2,4-dinitroanisole (DNAN), nitrotriazolone (NTO), and nitroguanidine (NQ). The nominal composition is 43.5 wt% DNAN, 36.8 wt% NQ, and 19.7 wt% NTO. Trace amounts of N-methyl-p-nitroaniline (MNA) are included in some formulations to aid in processing. A formulation containing about 24 wt% aluminum and 76 wt% IMX-101 is called ALIMX-101 and is being investigated as an insensitive replacement for H6 and PBXN-109 in Mk82-style bombs.
+A Family of Insensitive Melt Cast Explosive Formulations: Insensitive Melt Cast Explosives manufactured at Holston Army Ammunition PlantThis table is closely modelled on FormulationKey IngredientsReplacesPurposeQualification Status (2012)IMX-101DNAN + NTO + NQTNTArtillery and other large caliber munitionsMaterial qualified; Type qualified for 155mm M795, on-going for 155mm M1122 and 105mm projectilesIMX-104DNAN + NTO + RDXComp BMortar applicationsMaterial qualified; Type qualification on-going for 81mm mortar, 60mm & 120mm to followPAX-48DNAN + NTO + HMXComp BMortar and tank ammunitionMaterial qualified; Type qualification achieved for 120mm IM HE-T tracer round (NAMMO)OSX-12DNAN + NTO + RDX + AlPAX-28High blast applicationsMaterial under evaluationPAX-21 Picatinny arsenal explosiveDNAN + RDX + AP + MNA (N-methyl-p-nitroaniline)Main fill for the 60mm M768 mortar roundsBeing used in theaterPAX-41DNAN + RDX + MNAMain fill for the Spider Grenade, thus a low critical diameter is required.
The performance of PAX-28, a thermobaric, containing a mixture of RDX, DNAN, Al, AP and MNA was found to have an indoor explosive equivalency factor of 1.62 when compared to Composition B. OSX-12 is being studied as a replacement to .
Processing Like Composition B, IMX formulations are melt-castable without thermal degradation, and are thus processed into munitions by a melt pour process starting with a batch melt kettle heated by a steam heat exchanger.
See also M107 projectile XM1128 projectile
Further reading The Characterization of IM Explosive Candidates for TNT Replacement Explosive Ingredients and Compositions for the IM M795 Artillery
References