This network of open pores can be impregnated with a variety of materials, from plastics to metals to ceramics, and the final shape of the filled open-pore composite is formed during the processing. Finally, the matrix can have a predetermined shape and size formed by an open honeycomb core made of metal impregnated with a ceramic filler for high-temperature applications. No attempt is made to introduce the element of time in these figures, other than to state that the time a material is subjected to these extremes in temperature is a critical factor that must be taken into consideration in any design. C continually and 427 o C intermittently. Epoxies are the chief TS, but thermoset polyester is a strong contender, particularly for auto applications.
Epoxies have a wide range of properties.
Intermediate modulus epoxies are used in hybrids. Polyimides find use for extended operations near 260 o C and above. TS polyester, formulated to be hard, brittle, or tough, is used with chopped glass in many applications. User friendly prepreg resins have better controlled reactivity and an extended out-time. Structural film adhesives resist moisture in the bond line and are extremely resistant to severe environmental exposure.