Military electronics

The exponential distribution has proved to be a reasonable failure model for electronic equipment (8—13). Since the field of reUabiUty emerged, owing to problems encountered with military electronics during World War II, exponential distribution has had considerable attention and apphcation. However, like any failure model, it has limitations which should be well understood. 

Luenberger, D.G. (1964) Observing the State of a Linear System, IEEE Trans. Military Electronics, MIL-8, pp. 74-80. 

DATA BOUNDARY Electronic components used in military electronic systems and equipment. 

Military Handbook 217E (MIL 217E) establishes uniform methods for predicting the reliability of military electronic equipment and systems. There are two methods of reliability predictions, namely parts count and parts stress analysis. 

RAC publications include data summaries for specific component types, such as hybrid microcircuits, small, medium and large-scale integration digital devices, linear and interface devices, digital monolithic devices, and discrete semiconductors. In addition, there are reliability and equipment maintenance data books that provide the failure and repair time data on military electronic equipment by application such as subsystem. 

World War II helped shape the future of polymers. Wartime demands and shortages encouraged scientists to seek substitutes and materials that even excelled those currently available. Polycarbonate (Kevlar), which could stop a speeding bullet, was developed, as was polytetrafluoroethylene (Teflon), which was super slick. New materials were developed spurred on by the needs of the military, electronics industry, food industry, etc. The creation of new materials continues at an accelerated pace brought on by the need for materials with specific properties and the growing ability to tailor-make giant molecules macromolecules—polymers. 

Polymer-clay nanocomposites (PCN) are a class of hybrid materials composed of organic polymer matrices and organophilic clay fillers, introduced in late 1980s by the researchers of Toyota (Kawasumi, 2004). They observed an increase in mechanical and thermal properties of nylons with the addition of a small amount of nano-sized clays. This new and emerging class of pol miers has found several applications in the food and non-food sectors, such as in constmction, automobiles, aerospace, military, electronics, food packaging and coatings, because of its superior mechanical strength, heat and flame resistance and improved barrier properties (Ray et al., 2006). 

Electrical connectors and components (e.g., switches fuse, switch box, computer housing, switchboard electrical connectors, stereos, business machines, military electronics)... 

Information Sources , Gale Research Co, Detroit (1967), 135-143 14) S.E. Mautner, Military, Electronics, and Aerospace Handbook on Reuseable Protective Packaging , Kayar Publg Co, USA (1967) 15) G.R. Buck et al, A... 

Figure 10 Main air cooling schemes for military electronics...

Anon, Reliable Military Electronics , ArvICP 7C8-124, Ibid (1976)... 

World War II increased both the demand and the number of applications for plastics. Just prior to the war, plastics were not only developed as substitutes for materials which were in short supply, notably rubber and gutta percha, but also to out-perform the then available plastics. Wartime demands encouraged scientists to develop polymers that could meet the demands of the military, electronics and food industries. Before 1940, plastics had mainly been used to make decorative and ephemeral pieces, but the war demanded more performance-based... 

Military electronics may be ground-based or airborne but, in either case, must be capable of withstanding the harsh extremes of terrestrial environments. Ground-based electronics must also be resistant to fungus and other microorganisms, salt spray (if... 

O. Hnojewyj and M. Murdoch, Ultraviolet Curable Materials for Military Electronic Applications, Paper presented at Third Annual U.S. Navy Best Practices Workshop, San Diego, CA, September 1989 (authors from Litton Industries, Applied Technology Division, Sunnyvale, CA). 

Reliability data are available for many adhesives used in space environments for different orbits, different radiation, and different thermal-vacuum conditions. These data are available from approved materials and processes lists from NASA or from contractors for programs such as the Space Shuttle, Space Station, GPS, Hubbel telescope, and numerous satellite systems, some of which have been in orbit for over ten years. Adhesives used in military electronics have also been proven highly reliable in fighter planes, navy ships, ground and air communication systems, and navigation systems. 

Industrial or engineering ceramics. This class includes a wide range of finished products and raw materials for biological, military, electronic, automotive, aerospace, and high-temperature uses. Typical materials include alumina, zirconia, titan-ate, silicon carbide and nitride, SiAlON, and mixtures of rare earths. 

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