ABSTRACT
For most composites in use today, the individual lamina (i.e., the individual layer or ply) is the basic unit or building block, whether it is in the design, the analysis, or the fabrication process stage. This lamina may be a unidirectional prepreg, a fabric, a chopped-strand mat, or another fiber form, with or without the matrix present prior to laminate fabrication. However, some composites are not fabricated of individual layers. As discussed in Chapter 3, such alternate processes include resin transfer molding (RTM), and vacuum-assisted resin transfer molding (VARTM). However, the resulting composites are typically still nonhomogeneous and anisotropic in terms of strength, stiffness, and physical properties. Thus, even in these cases the designed composite component still consists of individual layers (or regions) of differing material properties.
