مجله تحقیق و توسعه مواد پرانرژی
سال هشتم شماره 2 (پیاپی 17، پاییز و زمستان 1391)

Interior ballistic analysis is very important because ballistic cycle is extremely rapid and measuring process into the gun tube is very difficult. In this article, effect of co-volume considering have been investigated by analytical solution. This parameter is related to interaction between molecules in gaseous phase at high pressure and high temperature. The present model is based on Corner method with linear burning rate. Noble-Able equation of state was used at this model instead ideal gas equation of state. Available volume for propellant gases is reduced as a result of considering co-volume. Therefore pressure and muzzle velocity increased. In this research work, new formulations for analyzing spherical propellant grains have been developed.

Nowadays; utilization of simulation methods for prediction material behavior particularly in the development of powder metallurgy is increasing. Many of the physical and mechanical properties have a direct relationship with the final density. In the process of producing propellant by compaction methods, the density of resulted material is an important factor. It has a great effect on the explosion power and explosive sensitivity of propellant. Usually, in the propellant compaction process, try and error method and experimental method are used. In this paper has investigated existing models for simulation of compaction process that includes macromechanical and micromechanical models. Drucker-prager model is widely used model in the simulation of compaction process. It is capable for density distribution in compacted sample.

1,3,5-Triamino-2,4,6-Trinitrobenzene (TATB) is an explosive that possesses excellent thermal stability, suitable density and lower sensitivity than the other standard explosives such as TNT. These properties make TATB an attractive candidate for using in military applications such as using in rocket warhead. In civilian sector TATB is used for deep oil well explorations where heat-insensitive explosives are required. TATB is also used for producing benzene hexamine, an intermediate in the synthesis of new and advanced materials. This compound used for preparation of organic ferromagnetic salts and heterocyclic molecule such as 1,4,5,8,9,12- haxa azatriphenylen. In this paper the chemical, physical and explosive properties of TATB have been reviewed and also analysis, identification and purification methods of TATB have been exposure. In addition, all synthesis methods of TATB have been introduced and their advantages and disadvantages have been compared. Finally the suitable method has been suggested.

The energy level and performance of fuel-air explosives (FAE) will be increase significantly with adding metal and non-metal energetic solid particles. Importance of homogeneous and uniform distribution of these solid particles into liquid fuel causes that the colloidal characteristic of gels and gelling of these kinds of fuels has been considered as an advantage. On the other hand, because of the difference between solid particles and liquid fuel specific gravity, phenomena that called phase separation and the settling of solid particles usually take place in these compounds that is mainly due to the outer forces effect such as gravitational force and weapon acceleration. In this paper, we introduce the fuel-air explosives and advantages of their gelling initially. Then we have described different parameters affected on phase stability in FAE gelled fuels with and without energetic solid particles such as particle size and amount of gelling agent, size and density of added solid particles and etc. However the stabilizing and phase stabilization methods have been studied for FAE gelled fuels.

Gel propellants are an optimum state from of liquid propellants. The advantages of liquid and also solid propellants are kept in gel propellants but their disadvantages were mainly omitted. According to published informations, different kinds of gellants are used to make gel propellants. Among them, Silica is known as a good gellants for IRFNA oxidant and kerosene fuels. This gellant due to Si-OH groups on its surface can produce hydrogen bonds when mixed with mentioned oxidant and fuels which lead to production of a stable physical gel. Cellulosic gellants are suitable for amine fuels. They produce physical gel through hydrophobic interactions of substituted groups on glucopyranose units and also by hydrogen interaction. In this paper the types of gellants and gelation mechanism are discussed.

One of the important components in the solid propellants is plasticizer which is used to simplifying the process and increase flexibility of the propellant. Dioctylsebacate (DOS) as a neutral plasticizer compound is used in solid propellant formulations. In this paper, we investigate the physicochemical properties and different synthesis methods of ِDOS. In continuation an experimental method for the preparation of this compound from the raw material of plant origin Castor oil followed by saponification reaction with 2-Ethyl hexanol was introduced. Under optimal conditions, high purity product of dioctyl sebacate was obtained in 85% yields. The structure and purity of the dioctyl sebacate were approved by using analytical instruments GC, IR, NMR, CHN and Mass.

One of the main ingredients in composite propellants fuels is metal, that been added to increase the efficiency of high explosives. Recently, it is widely used in the propellant of missiles, rockets, gun and in artillery propellants with particularly long-range performance. The first characteristics of boron-containing propellants are high energy density per unit mass of propellant that result is increases in specific impulse of composition. Also, according to the ballistic characteristics of the combustion products of boron, unlike the aluminum (traditional metallic fuel), show optimum ballistic properties. Addition of boron and replacing it instead of aluminum significantly increases the performance of rockets and missiles propellants. According to the points already mentioned, elemental boron can be considered as a replacement by aluminum element; so in this article, the mechanism of combustion behavior of metallic boron as a fuel will be studied.