Processing of Selectively-Discontinuous-Fiber (SDF) Composite Materials

This proposal is directed at creating discontinuous unidirectional composite from continuous unidirectional prepreg. The process, Selectively-Discontinuous-Fiber (SDF), introduces micro-cuts in preimpregnated unidirectional materials at specified locations. This process will allow unidirectional composite prepreg to be used for the fabrication of complex-compound components that have been impossible in the past. Standard continuous unidirectional composite materials have limited capability to accommodate the small radii often required in intergrally-stiffened structures or to form the complex-compound shapes without sacrificing mechanical integrity. The process uses established technology with minor modifications to accommodate preimpregnated material and can be done on "off-the-shelf" prepreg. This process is truly unique in that it can introduce the micro-cuts at specific locations on the impregnated material, producing selectively discontinuous material.