Aerospace applications, glass composites

The special needs of the space program motivated the search for composite materials for other reasons also. For example, during tests of the first Atlas ICBM (intercontinental ballistic missile), engineers were concerned that the rocket s metallic components would not survive the missile s reentry into the atmosphere they feared it would melt down because of the intense heat to which it was exposed. By the late 1950s, therefore, aerospace researchers had begun to look for satisfactory substitutes for metal alloys for such applications. With that research, the modern held of composite design was horn. One of the first composites tested consisted of pieces of glass embedded in melamine, purported to be the first composite material developed for aerospace applications. 

The applications of glass/glass-ceramic matrix composites (CMC) can be divided into two specific categories aerospace applications and non-aerospace applications. In aerospace applications, performance is the prime consideration, while in non-aerospace applications cost-effectiveness is paramount. The characteristic properties of materials for aerospace applications should be... 

A good example of large-size fiber-reinforced components in aerospace application is the radome covering the underbelly radar on the Hercules transport aircraft. It is made from very thin polyethylene sulfide (PES) film interleaved with PES-impregnated glass fiber cloth, which is subsequently hot molded in a closed die. The composite radome, nearly 1 m in diameter and 6 mm thick, weighs only 10 kg. 

Hybrid aluminosilicate glass matrix composite with Nicalon fibre and SiC particulate reinforcement Fracture strength 778 MPa-827 MPa (depending of SiC particulate content) High-lemperature aerospace applications [74]... 

Although composites of glass cloth with polymeric resins have been common for several decades, the development of aerospace technology in the 1950 s and 1960 s led to an intensive effort to understand composites better and to optimize their physical behavior. Since weight must be kept to a minimum in aerospace applications, considerable attention was given... 

Polymers reinforced with cellulose fibers have received much attention in recent years because of their low density, nonabrasive, combustible, nontoxic, low cost and biodegradable properties. Several authors have reviewed recent advances in the use of natural fibers in composites like flax [ 1 ], jute [2,3], straw [4], kenaf [5,6], coir [7-9], fique [10], among others. Natural fibers have been used to reinforce thermoplastics and thermosets polymers in automotive and aerospace applications [11]. The influence of surface treatments of natural fibers on interfadal characteristics was also studied [12-17], and Joshi et al. [18] compared the life-cycle environmental performance of natural fiber composites with glass fiber composites. In this study, natural fiber composites were found to be environmentally superior in most applications. 

S-glass A magnesia-alumina-silicate composition with an extra high strength-to-weight ratio, more expensive than E-glass and used primarily for mUitaiy and aerospace applications. 

S-glass composites are used in the majority of aerospace applications. The glass is used to the greatest extent in combination with epoxy resins. The resultant composite maintains excellent structural characteristics up to the degradation of the epoxy resin. A primary supplier of S-glass fiber is Owens Coming. 

Epoxy adhesives are widely used in most industries for the structural bonding of most types of materials (metals, wood, plastics, composites, ceramics, glass, concrete, masonry, etc). Primers may be recommended for some materials. They are also used to repair structures bonding patches and crack-filling. Some adhesives are specifically designed for aerospace applications or specialised mechanical and electrical assembly. 

Compared to ultra-high strength conventional polymers, the temperature stability of LCPs is a defining characteristic that makes them effective in many applications. Like other organic polymers, they are characterized by very low densities when compared to inorganic materials such as glass and metals. This means that the tensile strength-to-mass ratios are very favorable for composite applications, and they can therefore be used in aerospace applications. ... 

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