IMX-101
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.[1][2][3][4] 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, it is believed 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.[5] The new explosive will cost $8 per pound, compared to $6 per pound for TNT.[6] As of 2023, IMX-101 filled shells are being used in the 2022 Russian invasion of Ukraine.[7]
Time Magazine called IMX-101 one of the "50 best inventions of 2010".[6]
Composition
IMX-101 is composed of 2,4-dinitroanisole (DNAN), nitrotriazolone (NTO), and nitroguanidine (NQ).[5] The nominal composition is 43.5 wt% DNAN, 36.8 wt% NQ, and 19.7 wt% NTO.[8][9][10] Trace amounts of N-methyl-p-nitroaniline (MNA) are included in some formulations to aid in processing.[11][12] A formulation containing about 24 wt% aluminum and 76 wt% IMX-101 is called ALIMX-101 and is currently investigated as an insensitive replacement for H6 and PBXN-109 in Mk82 style bombs.[13]
Formulation | Key Ingredients | Replaces | Purpose | Qualification Status (2012) |
---|---|---|---|---|
IMX-101 | DNAN + NTO + NQ | TNT | Artillery and other large caliber munitions | Material qualified; Type qualified for 155mm M795, on-going for 155mm M1122 and 105mm projectiles |
IMX-104 | DNAN + NTO + RDX | Comp B | Mortar applications | Material qualified; Type qualification on-going for 81mm mortar, 60mm & 120mm to follow |
PAX-48 | DNAN + NTO + HMX | Comp B | Mortar and tank ammunition | Material qualified; Type qualification achieved for 120mm IM HE-T tracer round (NAMMO) |
OSX-12 | DNAN + NTO + RDX + Al | PAX-28 | High blast applications | Material under evaluation |
PAX-21 Picatinny arsenal explosive | DNAN + RDX + AP + MNA (N-methyl-p-nitroaniline) | Main fill for the 60mm M768 Mortar Rounds | Currently in-use in theater | |
PAX-41 | DNAN + RDX + MNA | Main fill for the Spider Grenade, thus a low critical diameter is required.[14] |
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.[12] OSX-12 is being studied as a replacement to PAX-28.
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.[15][16]
See also
- M107 projectile
- XM1128 projectile
Further reading
References
- "BAE IMX-101 Explosive Approved To Replace TNT In US Army Artillery". Archived from the original on 2010-08-07. Retrieved 2010-08-03.
- DTIC Background and Introduction to IMX-101, -102 and -103 Archived 2010-08-15 at the Wayback Machine
- The Application of New IM Explosive Candidates - DTIC Online Archived 2012-10-03 at the Wayback Machine
- "Army Approves Safer Explosive To Replace TNT". Archived from the original on 2010-08-20. Retrieved 2010-08-17.
- Allison Barrie (2013-03-26). "Bye bye, TNT: New generation of explosives for the Army". Fox News. Archived from the original on 2013-03-27. Retrieved 2013-03-26.
- Mark Thompson (2010-11-13). "Less Dangerous Explosives". Time Magazine. Archived from the original on 2013-05-25. Retrieved 2013-06-16.
- Ismay, John; Keyssar, Natalie; French, Lyndon; Taylor, Marisa Schwartz; Lieberman, Rebecca (2023-02-02). "How to Forge Shells for Ukraine's Artillery". The New York Times. ISSN 0362-4331. Retrieved 2023-02-02.
- "E.-C. Koch, Insensitive High Explosives: IV. Nitroguanidine - Initiation & Detonation, Defence Technol. 2019, 15, 467-487". Archived from the original on 2020-12-01. Retrieved 2021-01-25.
- This table is closely modelled on Virgil Fung; et al. (2012). "2012 IMEMTS, Las Vegas, NV (S2DSEA2012-0148) Process Improvement and Optimization of Insensitive Explosive IMX-101 2012 Insensitive Munitions & Energetic Material Technology Symposium" (PDF). U.S. Army. Archived (PDF) from the original on 2021-01-25. Retrieved 2021-01-25.
- Cuddy, Michael F.; Poda, Aimee R.; Chappell, Mark A. (2014). "Estimations of Vapor Pressures by Thermogravimetric Analysis of the Insensitive Munitions IMX-101, IMX-104, and Individual Components". Propellants, Explosives, Pyrotechnics. 39 (2): 236–242. doi:10.1002/prep.201300069.
- Rao, Balaji; Wang, Wei; Cai, Qingsong; Anderson, Todd; Gu, Baohua (2013). "Photochemical transformation of the insensitive munitions compound 2,4-dinitroanisole". Science of the Total Environment. 443: 692–699. Bibcode:2013ScTEn.443..692R. doi:10.1016/j.scitotenv.2012.11.033. PMID 23228715.
- "Insenstive High Explosives (IHE)". Archived from the original on 2014-07-08. Retrieved 2014-06-04.
- "The Latest from Defense Systems Information Analysis Center" (PDF). Defense System Digest. March 12, 2019. Archived (PDF) from the original on June 11, 2020. Retrieved January 25, 2021.
- "DEVELOPMENT & OPTIMIZATION OF A PRODUCTION METHOD FOR MANUFACTURING PAX-41" (PDF). Archived from the original (PDF) on July 19, 2013.
- "IMX-104 High Explosive (HE) Loading of 81mm & 120mm Mortars" (PDF). Archived from the original (PDF) on 2014-06-04.
- Ismay, John; Keyssar, Natalie; French, Lyndon; Taylor, Marisa Schwartz; Lieberman, Rebecca (2023-02-02). "How to Forge Shells for Ukraine's Artillery". The New York Times. ISSN 0362-4331. Retrieved 2023-02-02.