Civil application

Explosives are used for constructive as well as destructive purposes for both military and civil applications. There are several ways of classifying explosives and a few important ones are ... 

However, it is difficult to distinguish between military and peaceful applications of military weapons. Here are a few examples which illustrate that it is extremely difficult to classify them under military or civil applications. 

Despite the fact that LA, LS and tetrazene suffer from serious drawbacks, they are still being used in detonators and cap compositions for military and civil applications. Thus LA, LS and tetrazene are the most commonly used primary explosives at present and research is in progress in order to find out suitable substitutes free from such drawbacks. The aim of research in initiatory explosives has all along been to get less sensitive, more compatible, more stable and more efficient material so that safety in manufacture and handing is ensured. 

In the initial stages, the end use of n-Al was largely dominated by defense-related applications. Small caliber primers for defense munitions, additives for solid and hybrid rocket propellants, enhanced lethality explosives and pyrotechnics and thermite-based weapons are some typical military applications of n-Al powder. The use of n-Al powder has also been reported for some civil applications such as fireworks, automotive inflators and airbag initiators as well as drilling and oil exploration. 

Cogeneration means that there are two marketable products electricity and heat. The heat is usually in the form of steam and is sold to process industries or for civil applications (district heating) thus, the latent heat of the steam is not wasted, but utilized. The steam user should be near the power plant in order to reduce steam transportation losses and the demand for steam should be continuous. The steam can be obtained from back-pressure steam turbines or from extraction in the intermediate- and low-pressure (IP or LP) stage of the turbine. 

Secondary explosives (also known as high explosives = HEs) unlike primary explosives can not be initiated simply through heat or shock. In order to initiate primary explosives have to be used, whereby the shockwave of the primary explosive initiates the secondary. However, the performance of the secondary explosive is usually higher than that of the primary (see Tab. 2.1). Typical currently used secondary explosives are TNT, RDX, HMX, NQ and TATB (see also Tab. 1.2) and, for civil applications, HNS and NG e.g. in the form of dynamite for commercial use. 

As previously stated, this discussion is valid for homogeneous explosives, such as the ones used in the military, since their reactions are predominantly intramolecular. Such explosives are often referred to as ideal explosives, in particular when they can be described using the steady state model of Chapman and Jouguet. In heterogeneous explosives (non-ideal), which are currently used in civil applications, intermolecular (diffusion controlled) mechanisms are predominant for the air bubbles, cavities or cracks (etc.). As a general rule detonation velocities increase proportional to the diameter. 

This book is concerned with both the civil applications of high-energy materials (e.g. propellants for carrier or satellite launch rockets and satellite propulsion systems) as well as the many military aspects. In the latter area there have been many challenges for energetic materials scientists in recent days some of which are listed below ... 

As microwave devices above 50 GHz are rarely used in civil applications, a useful design is necessary for the ACC radar. The development must concentrate on reasonable cost, high environmental robustness, and (very important for the automotive application) small size. 

Since that time the objects of the industry have changed from military to civil applications and three generations of plant have been constructed and operated. The United Kingdom reasonably can claim to have technical and industrial competence in all of the aspects of the nuclear fuel cycle, although the experience of the final disposition of highly radioactive waste is limited and affected necessarily more by social and political factors than by technology. 

As a result of the defense industry conversion a number of small-scale power projects became available for civil applications. These Projects were developed for marine and submarine fleet, spacecraft and other scientific purposes, being notable for their novelty and advanced technological level in comparison with similar projects either in Russia or abroad. 

Among more civil applications of this theory, we may use this method to plan better drills and better steel plates, as well as about other micro-tools which have a bright future. 

PU elastomers processed by RIM are widely used in automotive industries. Examples are bumper covers, external body panels, modular windows and exterior and interior trims. Such elastomers are also used in eqnipment housing, sports equipment and furniture. Castable PU elastomer sheets are used as vibration damping materials and acoustic window materials for various naval and civil applications. Because of higher water resistance, PU elastomers are preferable as encapsulant materials for underwater electronics. 

Civil application results also in substantial fatigue loading, in the sense that prolonged service may lead to failure at stresses largely inferior to the yield point. Fatigue may be mechanical (for example, due to vehicle traffic), thermal (from seasonal and diurnal variations in temperature) or chemical... 

For these reasons, nowadays epoxy resins find application in several fields, e.g. coatings, electrical and electronic insulation, adhesives and construction, and as matrices for FRP in automotive, nautical, aerospace and civil applications. 

In this chapter, informative discussions, explanations and verifications have been presented on the issue of stresses, their categories, significance and characterization in FRP strengthened civil applications. Throughout the chapter, particular emphasis has been given to the lap-shear and normal stresses within the interfacial adhesive layer of externally bonded FRP/steel adherends, since this component (i.e. interfacial adhesive) and adherend (i.e. steel) of such FRP joints represent, in terms of these stresses, the most likely failure location and ultimate capacity of FRP adhesive joints, respectively. Some useful key conclusions can be drawn based on all the issues presented in this chapter ... 

---