High Temperature Structures

They are used as high-temperature structural adhesives since they become rubbery rather than melt at about 300°C. 

The covalently-bonded silicon carbide, silicon nitride, and sialons (alloys of Si3N4 and AI2O3) seem to be the best bet for high-temperature structural use. Their creep resistance... 

McLean, M. (1996) in High-Temperature Structural Materials, eds. Cahn, R.W., Evans. 

Yamaguchi. M. (eds.) (1996) Symposium on Intermetallics as new high-temperature structural materials, Intermetallics 4, SI. 

The intermetallic alloy NiAl is discussed as a potential base alloy for high temperature structural materials. Its use is currently limited by low room temperature ductility and fracture toughness. Consequently, substantial research efforts have been directed towards understanding its mechanical behaviour [1, 2] so that detailed experimental [3, 4, 5] and theoretical [6, 7, 8] analyses of the deformation of NiAl are available today. 

Gonsalves, K. Agarwal, R. presentation at "High Temperature Structural Composites Synthesis, Characterization Properties" Symposium May 87, sponsored by MRS, NJ. 

In many nonstoichiometric solids high-temperature structures contain disordered defects, but, as in the previous example, these order or form aggregates at lower temperatures. If this aggregation could be suppressed, low-temperature ionic conductivity would be enhanced. An example of this strategy is provided by compounds with the... 

Lager G. A. and Meagher D. M. (1978). High temperature structural study of six olivines. Amer. Mineral, 63 365-377. 

Winter J. K., Okamura F. P. and Ghose S. (1979). A high temperature structural study of high albite, monalbite, and the analbite-monalbite phase transition. Amer. Mineral, 64 409-423. 

Cured Bisbenzocyclobutene (BCB) terminated resin systems exhibit good mechanical properties with 70Z to 85X retention of properties at 260 C and high thermal stability. The Materials Laboratory has studied these materials for use as high temperature structural matrix resins in composites. They are well suited for this use since they do not require the use of catalysts and cure without the evolution of volatiles. 

An endothermic (4.18kJ mol ) structural transition is observed at 118°C from the orthorhombic low-temperature structure to the hexagonal high-temperature structure. The high-temperature structure melts at 287 °C with a latent heat of 7.56 kJ mol . Both transitions are reversible, although a small hysteresis in temperature was observed. 

Harris and Meibohm suggested the space group Pcmn for UBH4 at room temperature, which turned out to be wrong [82]. The low- and high-temperature structures were investigated by means of synchrotron X-ray powder diffraction [83, 84]. 

Figure 5.42 Low-and high-temperature structure of Li BH4 determined by means ofX-ray diffraction.

Varghese OK, Gong DW, Paulose M, Grimes CA, Dickey EG (2003) Giystallization and high-temperature structural stability of titanium oxide nanotube arrays. J Mater Res 18 156-165... 

Silicon carbide fibers have been used with aluminum, titanium, and coball-based superalloys for high-temperature structures and engine components. 

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