Curve for Tetryl

Similar tests were conducted for Tetryl of loading d 1.60 and for TNT of d 1.55. Their luminosity curves for deton in air at atm pressure are given below. The left curves were taken using optical filters with transmission maxima at A=6870A, while the right ones used A= 4510 (Ref 5, Progr-Rept, Apr-June 1949) 

In ProgrRept July-Sept 1949 are given photographs of luminosity curves for deton of PETN of loading d 1.40 in air as recorded on a sweep trace of 10 20 microsec duration In ProgrRept Apr-June 1950 is given the following table of relative luminosity of detonation peak for three expls in pellet form  

In ProgrRept Oct-Dec 1950 are given relative luminosities of unsheathed expls PETN (of d 1.50) - 1.0, ComD C-4 (plastic) -3.0 

In ProgrRepts Oct-Dec 1952 Jan-March 1953, it was stated that much of the luminosity which accompanies deton is due to the shock wave in the ambient medium. 

The use of certain surrounds (such as propane) eliminates or substantially reduces these luminosities which are undesirable if one is attempting to observe the radiation emitted by the deton products in the deton wave 

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Figure 4.51. The mass velocity-time curve for Tetryl obtained by the EPVG method (After Philippart, 1985)...

Examples of u vs time curves for TNT and Tetryl, obtained by Jacobs Edwards (Ref 4) are diown in Figs 4—6. As expressed by these authors The determination of a CJ particle velocity and a reaction zone time by the EMV gage has required judgment to select the point on the curves which one would associate with the termination of the reaction. This is not always a simple matter. In our pressed TNT records there was little choice but to take the time at which the u—t curve levels off as the CJ... 

Fig 3 DTA curve (solid line) and pyrolysis (thermal conductivity) curve (dashed line) for Tetryl... 

Fig 4 Detonation vs Charge Diameter Curves for Coarse Tetryl... 

Ammonium picrate is of a very high order of stability. In the lOO C heat test, 0.1 percent is lost in the first 48 hours and 0.1 percent in the second 48 hours. No explosions occur in 100 hours. In the 130"C heat test there is no acidity or explosion in 300 minutes. The vacuum stability test at 100°C produced 0.2 cubic centimeters of gas in 40 hours, at 120°C, 0.4 cubic centimeters of gas are produced, and at 150°C, 0.4 cubic centimeters of gas are produced. The material has been found to withstand storage at ordinary temperatures for a period of twenty years with no evidence of deterioration, and at 50°C for more than five years without marked deterioration. Moisture increases ammonium picrate s reactivity with metals such as lead, potassium, copper, and iron. The compounds produced are extremely sensitive. This reactivity requires that all projectiles loaded with this material have contact areas covered with acid proof paint. At 100°C ammonium picrate is compatible with TNT or black powder but undergoes reactions with nitroglycerin, nitrocellulose, PETN, or tetryl. Figure 8-42 shows the DTA curve for ammonium picrate. 

There are also given curves of relationship betw temps of deton and densities for PETN, Tetryl TNT, based on the values obtd by P. Caldirola, JChemPhys 14, 738-40(1946), as compared with the values obtd at BurMines (See Fig 1 of the progr rept)... 

The isothermal method for such expls as PETN, RDX, NG and Tetryl is complicated by autocatalysis to such an extent that one cannot determine the intrinsic (pure explosive) decompn rate from the logw vs t curves and their change with temperature. Hence, the results obtd by the adiabatic(sensitivity) methods may be more reliable from this viewpoint (Ref 8, p 177)... 

Lafitte (Ref 2), vel of deton generally increases with the diam of cartridge up to a maximum value, above which the vel remains constant. This is true for PA, RDX and for AN/Tetryl mixts contg more than 10% Tetryl, but for some other expls, such as PETN and Tetryl, the curve of deton vel vs cartridge diam increases at first, passes thru a maximum, then decreases and, after passing thtu a minimum, rises again... 

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