Hmx, The Mechanical Properties Of Tatb-based Polymer Bonded Explosive (pbx) Md Simulation Study

HMX(cyclotetramethylene tetranitramine) and TATB(1,3,5,-triamino-2,4,6-trinitroben zene) are high explosives widely used with better comprehensive properties. In this dissertation, by applying the molecular dynamics method, systematic computation and simulation are carried out to polymer bonded explosives (PBXs) composed of HMX, TATB and a series of fluorine-containing polymers. The effect of those has been discussed to obtained in exploring the regular relations between structures and properties.1. Molecular dynamics (MD) method using COMPASS force field and elastic mechanics fundamental principles have been employed to simulate and investigate the mechanical properties of pure HMX crystal, TATB crystal and their PBXs, i.e. HMX and TATB blended with a series of fluorine-containing polymers (PVDF, PCTFE, F2311, F2314). It is found that the mechanical properties can be improved indeed by blending with fluorine-containing polymers in small amounts.2. By COMPASS force field MD simulation, the elastic coefficients, and the effective isotropic mechanical properties such as moduli, Poisson's ratios, and Lame coefficients of pure TATB and TATB/F2311 PBX at the temperature of 245K-495K are obtained. It is found that not only rigidity decreases and the flexibility increases with the increasing temperature but also at the same temperature the flexible property of the PBX is better than that of the pure TATB.3. The mechanical properties of mixed explosive which consist of TATB crystal and β-HMX crystal has been simulated by molecular dynamics(MD) and COMPASS force field at NVT and NPT ensemble by DISCOVER model block in the Materials Studio software package. The results show that the mechanical properties of β-HMX can be effectively improved by adding a little amount of TATB. The outcomes which obtain from NVT and NPT ensemble show similar parellel trend. At the temperature of 245K to 345K the mechanical properties of HMX/TATB mixed explosive remain unchanged. When the temperature rise to 395K, the rigidity decreases and the flexibility increases.