Phase Behavior in TNAZ-Based and Other Explosive Formulations
Abstract
The best predictor of the extent of eutectic formation between explosive ingredients is the difference between their reciprocal melting temperatures (r2 > 0.86 among 61 examples). Though the basis for predicting eutectic behavior from thermodynamic relationships such as van't Hoff's equation has come to be recognized in recent years, the correlation to melting point differences as the major contributor to this behavior seems to have been unrecognized in the energetic materials community. The correlation for binary compositions has the form: InX(solute)/X(solvent) = -4314.48 delta(T sub m-1) + 0.0363, where solvent is defined as the lower-melting component. 'Eutectics' between TNAZ and HMX and between TNAZ and 2,4-dinitroimidazole have been measured experimentally as essentially only melting point depressions due to <5% of the higher-melting ingredient as a minor constituent. The observation of this result from the TNAZ-HMX system led to the discovery of the correlation described above, which was confirmed by measurements of the new systems TNAZ-2, 4DNI and TNAZ-tetryl. The binary systems with HMX and with 2,4-DNI are predicted to contain 2.13 mol% and 2.33 mol%, respectively, according to the new correlation. The TNAZ-tetryl system was determined to have a eutectic temperature of 81.05 deg C (DSC onset). The predicted composition based on known enthalpies of fusion is 65/35 TNAZ/tetryl. TNAZ, Phase diagrams, Formulations, Eutectics, Explosive, 2,4-DNI.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 30, 1994
- Accession Number
- ADA286004
Entities
People
- Gary Burr
- John W. Fronabarger
- Robert D. Chapman
- Sally Kneuppel
- William B. Sanborn