ABSTRACT
Relaxation of the resin reduces both the transverse strength and effective long-term transverse modulus. High-performance composites require maximum possible fiber content. Stress in more than one direction must be handled by fibers laid in each direction, because a fiber composite can only sustain significant stress parallel to the fiber. A further category of composite materials is fiber-reinforced plastics. Structures and components are built to withstand specified conditions of load. Strain-at-failure may be estimated in design, but can only be fixed from failure tests of prototypes. Strain characterization of composite materials will then be considered in relation to the process of designing, prototyping, manufacturing, and monitoring a structure or component. Strain characterization must involve testing, but a simple listing of all tests used could be misleading. Design characterization tests are all those tests necessary to build up the data and methods required for the design of a structure or component.
