Sciencemadness Discussion Board

Defense Technical Information Center

grndpndr - 2-6-2008 at 01:22

Excellent site at least for a layman.Many Patents,#s and dates of filing.Recently a rash of bombings primarily in India are utilizing Ternary and Quarternary explosives utilizing RDX/HMX/ANFO and a quarternary explosive RDX/HMX/AN/ethylenediamine dinitrate. The Ternary and Quarternary HEs believe are patented but these particular explosies used in a bombing in Mombai, India were improvised from existing explosives.As an aside and a reason for the high death toll these devices were basically very large claymore mines,the US man. claymores contain = 1.5 lb
C4/1.5lbs 700 15 gr. steel balls/The Mombai devices contained 22 kg steel scrap/ similar amounts HE and there were 9 devices detonated at 6 locations; that being Religious shrines and Temples all within 15 minutes.signature of the Radical towel head tribalist's methodology of horror/intimidation .IMHRO

What caught my attention above other subjects discussed was this qoute. "These explosive compositions provide an unexpecedly high explosive output with a relatively low content of RDX and an equivalent output with much less RDX than coventional explosive mixtures."

Why this is the case wasn't explained but if ayone has input/answers Im all ears.

All HE obviously isnt compatible how would a layman without appreciable chemistry experience determine this w/o
actually making/mixng the HE comp. one was interested in then performing stability tests over weeks/ months? What sparks interest at the moment is Urea Nitrate/Picric Acid due to cost and ease of manufacture with easily available precursors labware.It need'nt be stable for years or even months though that would be a very important attribute. Finally is there some mathematical or Empirical method o f estimating det vel based on VOD of individual HE's?

[Edited on 2-6-2008 by grndpndr]

Boomer - 2-6-2008 at 08:10

The reason these mixes are higher performing than you would expect from their RDX content is likely that the small amounts of RDX make the AN behave more ideal than normal. In the usual AN/fuel mixes (not AN/TNT!) the VoD stays far behind the calculated ideal value.

Was the second mix cast? It reminds me of my test series with castable AN explosives that melt (sometimes far) below 100C. Some using AN/HDN/UN/GN/NaN/yougetthepoint needed only 10% RDX to transform them from undetonable rocker fuels into high-brisance, high-density explosives, punching clean holes into steel plates *without* bending the edges much. There's a thread about this by me on APC and some posts in some other thread here.

Most ideal explosives when mixed reach a VoD that mirrors their composition, by *volume*. If HMX had 9 km/s and TNT 7 km/s, a 50:50 mix *by volume* would shoot at 8 km/s. By weight and you get 7,92 km/s since the HMX would occupy only 46%, the TNT 54% of the space.

Unfortunately this does not work out if AN is a major component. There are also formulas to calculate the density and VoD of CHNO explosives from their formula, which dont work for AN mixes either. Again, there is a thread about those calculations, and s.o. even wrote a program that does the math for you. Search and you should find it.

grndpndr - 3-6-2008 at 08:25

Meaning the RDX component 'overdrives' , in a sense the other components such as a HV compound detonator would 'overdrive' some single component/binary explosives just as a detonator say a #2 commercial will detonate a certain binary explosive when a #6
commercial detonator is commonly used for full and a HV detonation as a minimum?
Similarly another relatively HV exp such as TNP could overdrive other blasting grade HEs.
The 50/50 while a great help as far as savings Im curious would lesser amounts 60/40 - 80/20 equal amatol theoretically in approximate increases in VOD. Appreciate the reply Boomer Ill search the threads as I should have done initially.Much more user friendly site than what I would hate too call a sister site.

grndpndr - 24-6-2008 at 20:11

I stumbled upon another I think related patent to the above in the sense a high velocity military explosive is added to an ANFO and in this case an emulsion and IIRC a water gel HE.
This patent US #6214140 (april 10 2001)deveopment of a new high energy blasting products usng demilitarized Ammonia picrate largely from large caliber naval cannon AP shells likely the great excess of 16in rifle AP projectles for battlehip use during ww2 some of which I believe carried 1000 lbs or more of HE in an APshell.
An anfo comp c0ntaning 20%-40% ammnium picrate "yellow D"To ANFO resuled in a dissapointing at least to my expectations for an increased det vel of only 1500-3000fps VOD + a 10%-%15 energy increase per unit volume.

STD +20% ammonium picrate 13,970 FPS
STD ANFO + 40% "yellow D" 15,430fps

in a 6in dia unconfined charge. To my mind disspointing increases for VOD for the amt of a high vel HE added quite different results that what was had with small amts of RDX
In the precedng patent.The only real advantage is of course the "green" disposal of an obsolete HE with an economic benefit
to the militry rather than the cost of incinerating a perfectly safe and valuable HE.