Aerospace programs

Reinforcement for metal-matrix composites with such metals as titanium, titanium aluminide, aluminum, magnesium, and copper. Applications are found mostly in advanced aerospace programs and include fan blades, drive shafts, and other components. 

The need for high-temperature-resistance fibers has arisen from demands of a number of industrial applications, as well as applications in aerospace programs. In many of these applications, the usual characteristics of organic-based fibers are desired, but the high temperature resistance of inorganic fibers is required. Thus, the fibers are expected to retain their structural integrity at temperatures of 300°C and above for considerable periods of time, but otherwise... 

The hopes began to fade when certain technical difficulties became apparent to the fuel cell community in the late 1960s and the early 1970s. Coupled to a parallel slowdown in aerospace programs, these obstacles almost led to the demise of fuel cell development for terrestrial applications. Appleby and Foulkes list four major problems ... 

The first specifications for adhesives were generated by the staff of NASA and the DoD who were prompted by the high reliability that was required of microcircuits used in aerospace programs. These specifications covered primarily die and substrate attachments for hermetically sealed integrated circuits, hybrid microcircuits, and multichip modules. Subsequently, with the increased use of surface-mount adhesives in the assembly of commercial printed-wiring boards and underfills for flip-chip devices, industry associations took the lead in generating the requirements and test methods. 

The polybenzimidazole fiber PBl was originally developed as a flame-resistant textile fiber for the US aerospace program. Because of their high oxygen index, they... 

The Atlas and Catalogue of infrared sources in the Magellanic Clouds was prepared from data obtained with the Infrared Astronomical Satellite (IRAS). IRAS was developed and operated by the Netherlands Agency for Aerospace Programs (NIVR), the U.S. National Aeronautics and Space Administration (NASA) and the U.K. Science and Engineering Research Council (SERC). 

Most major DOD agencies and contractors involved in the traditional weapons and aerospace programs have internal system safety organizations to plan and implement system safety efforts. The majority of the nation s system safety engineers tend to work for these organizations and, by and large, provide the membership for the System Safety Society. 

The total system safety effort for complex aerospace programs may involve several levels of organization. A typical six-level system safety effort may be organized as follows ... 

Student surveys show that students respond positively to woikshop environments where they have opportunities to conceive, design, implement, and operate engineering products, processes, and systems as part of the curriculum and in extracurricular activities. Students responses to these workspace initiatives has been uniformly positive at all participaling universities. As an example, surveys at MTT show that graduating students in the aerospace program feel that the redesigned workspaces have not only increased their abifity to learn disciplinary material, but also increased their positive feelings towards their classmates and their chosen profession. 

Initially refractory metals were applied mainly in the pure state. Extensive developments mainly driven by US aerospace programs led to a wide variety of alloys now commercially available. The compositions of solid-solution, precipitation- and dispersion-strengthened alloys are given in Table 3.1-108. Tungsten heavy metals and refractory-metal-based composite materials are not included here. 

In brief, reliability represents the overall probability of success (no failures) relative to a particular set of conditions of a specific service. Typically, in the case of military and aerospace programs, cell reliability exceeds 0.9999 probability of success. The conditions of operations in commercial or nondefense applications would be less severe and, therefore, reliability will be higher. 

This is a niobium-10, hafnium-1, titanium alloy. The composition is shown in Table 24.3. Application is primarily in aerospace programs because of its weight savings over other materials and its ability to withstand high stress levels and high temperatures up to 2700°F (1482°C). 

Aydin R, C tin E.N. 2009 Application of Mil-Std-785B Reliability program for systems and equipment development and production in aerospace programs. Demirel A., Qetin E. N. 2010 Reliability analysis process in UAS development programs. 

NASA, Elastomeric Sealants [in Aerospace Program], in Adhesives, Sealants, and Gaskets, Chapter 3, SP-5066, 1967. 

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