Aerospace industry use

Propellant compositions are also used in numerous "gas generator" devices, where the production of gas pressure is used to drive pistons, trigger switches, eject pilots from aircraft, and perform an assortment of other critical functions. The military and the aerospace industry use many of these items, which can be designed to function rapidly and can be initiated remotely. 

Engineering thermoplastics have also been used in preimpregnated constructions. The thermoplastic is thoroughly dispersed as a continuous phase in glass, other resins, carbon fibers (qv), or other reinforcement. Articles can be produced from these constructions using thermoforming techniques. For example, the aerospace industry uses polyetheretherketone (PEEK) in woven carbon-fiber tapes (26). Experimental uses of other composite constructions have been reported (27) (see also COMPOSITE MATERIALS, POLYMER-MATRIX). 

OTHER COMMENTS used in the shipbuilding and aerospace industries used in the chemical synthesis of pharmaceuticals, fire-resistant chemicals and gauge fluid used as a catalyst in polymer reactions. 

Improvements in both materials and processes have made RTM a viable option for aerospace manufacturing. However, it normally takes 10 to 15 years for a new technology to become accepted in the aerospace industry. Use of RTM began about 1998 when Lockheed Martin (Fort Worth, Texas, U.S.A.) selected RTM for many of the F/A-22 Raptor s structural components. RPs comprise approximately 27 wt% of the F/A-22 s structural weight (24% TS and 3% TP). RTM accounts for more than 400 parts, made with epoxy resins. The wing s sine wave spars were probably the first structural application of RTM composites in an aircraft. For a vertical tail on another Lockheed Martin aircraft, the RTM process reduced the part count from 13 to one, eliminated almost 1,000 festeners, and reduced manufacturing costs by more than 60%. 

In the aerospace industry uses include fuselage parts, both military and passenger, wings and control surfaces, engine cowls and landing gear doors. 

Several industries including the aerospace industry use rapid prototyping. Prototypic materials use polyethylene glycol having molecular weight of 600 daltons as plasticizer for poly(2-ethyl-2-oxaline), PEO, a polymer used for making prototypes. Plasticizer enhances overall water solubihty of PEO and its dissolution rate." ... 

The aerospace industry uses more adhesives based on epoxy resin chemistry than those based on any other. It is, therefore, worthwhile to examine several individual sectors within this industry, to illustrate how and where these adhesives are used. 

In wide sectors of industry there is a growing need of inspection methods which go without liquid coupling media. The excitation of bulk and surface waves by means of air-coupled ultrasonic probes is therefore an attractive tool for NDE. This is tme e.g. for the rapid scanning of large composite structures in the aerospace industry [1]. In other cases, the use of liquid couplants is prohibitive like the thickness measurement of powder layers. 

Electrical Applications. The largest application of PTFE is for hookup and hookup-type wire used in electronic equipment in the military and aerospace industries. Coaxial cables, the second largest appHcation, use tapes made from fine powder resins and some from granular resin. Interconnecting wire appHcations include airframes. Other electrical appHcations include computer wire, electrical tape, electrical components, and spaghetti tubing. 

The recovery of vanadium from these slags is of commercial interest because of the depletion of easily accessible ores and the comparatively low concentrations (ranging from less than 100 ppm to 500 ppm) of vanadium in natural deposits (147,148). In the LILCO appHcations the total ash contained up to 36% 20 (147). Vanadium is of value in the manufacture of high strength steels and specialized titanium alloys used in the aerospace industry (148,149). Magnesium vanadates allow the recovery of vanadium as a significant by-product of fuel use by electric utiUties (see Recycling, nonferrous LffiTALS). 

Boron filaments are formed by the chemical vapor deposition of boron trichloride on tungsten wire. High performance reinforcing boron fibers are available from 10—20 mm in diameter. These are used mainly in epoxy resins and aluminum and titanium. Commercial uses include golf club shafts, tennis and squash racquets, and fishing rods. The primary use is in the aerospace industry. 

Boron Trichloride. Approximately 75—95% of the BCl consumed iu the United States is used to prepare boron filaments by CVD (7). These high performance fibers are used to reinforce composite materials (qv) made from epoxy resius and metals (Al, Ti). The principal markets for such composites are aerospace industries and sports equipment manufacturers. 

Eor more demanding uses at higher temperatures, for example, in aircraft and aerospace and certain electrical and electronic appHcations, multifunctional epoxy resin systems based on epoxy novolac resins and the tetraglycidyl amine of methylenedianiline are used. The tetraglycidyl amine of methylenedianiline is currently the epoxy resin most often used in advance composites. Tetraglycidyl methylenedianiline [28768-32-3] (TGALDA) cured with diamino diphenyl sulfone [80-08-0] (DDS) was the first system to meet the performance requirements of the aerospace industry and is still used extensively. 

A recent survey of companies in the automotive and aerospace industry found that many companies are unaware of the benefits that can be gained from the utilization of quality tools and techniques. The adoption of BS EN ISO 9000 (1994) and Total Quality Management (TQM) strategies might be expected to increase the utilization of methods. However, the extent to which companies utilize methods is more strongly related to annual turnover than employee count, therefore the use of tools and techniques is dominated by large companies (Araujo et al., 1996). 

If one amino group in o-phenylenediamine is converted to an amide group by formic acid, the intermediate benzimidazole is formed. This reaction, conducted with a wide range of reactants, produces resins (polybenzimidazoles) used as high-temperature adhesives for laminates in the aerospace industry. Heat insulation is made by including tiny bubbles of silica and all... 

The drive for these additional requirements has come not from the suppliers but from users, such as the automotive, utilities, telecommunications, software, and aerospace industries which purchase millions of products and services used to produce the goods and services they provide to the consumer. Rather than invoke customer-specific conditions in each contract, the larger purchasers perceive real benefits from agreeing common quality system requirements for their industry sector. Quite often a supplier will be supplying more than one customer in a particular sector and hence costs increase for both the supplier and the customer if the supplier has to meet different requirements that serve the same objective. All customers desire products and services that consistently/ meet their requirements. While the physical and functional requirements for the product or service will differ, the requirements governing the manner in which their quality is to be achieved, controlled, and assured need not differ. Differences in quality system requirements may arise between industry sectors where the technology, complexity, and risks are different. 

Specifically, within the aerospace industry, for aircraft, the airframe manufacture itself is one of the major cost drivers, using the factors already addressed. Let s look at the character of how we would build an aerospace vehicle. There is typically a lot of manpower dependence. The industry itself is cyclic because the demands ebb and flow. There is typically little automation simply because of relatively low production rates, and there are very few customers. But, despite all those characteristics, there is typically also a large capacity that is founded on many highly skilled personnel, and the orientation is much more high tech than that of most other industries. Without product excellence as a driving factor, the whole industry would be an unworkable mess. 

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