Special Issue on Machining of CFRP Composites

There is a growing need for carbon-fiber-reinforced plastics (CFRP/CFRTP/GFRP) inthe aircraft, aerospace, and automotive industries due to their high strength-to-weightratio, high rigidity, and other features. Using these outstanding composites as machinecomponents requires machining with the desired configuration, accuracy, and surfaceintegrity. However, due to the composite structure of high-strength carbon fiber and theadhesive plastics, CFRP is difficult to machine without causing spalling or delamination,fluffing, fiber pullout, thermal degradation of the matrix resin, or other kinds of surfaceor subsurface damage. Rapid tool wear is also a serious problem that varies with thefiber orientation of the CFRP. In order to avoid these problems, various innovative or careful approaches have beentaken in drilling, trimming by milling, sawing, and grinding CFRP. Non-traditional machiningtechniques, including the use of abrasive waterjets, have been employed. Inthese techniques, the machining process, tool geometry, cooling system, and other machiningparameters are optimized. In addition, the influence of surface integrity on thetensile and/or fatigue strength or on other mechanical properties of CFRP has also drawninterest. In addition, regarded as a “machining process” in a broad sense, the press formingof continuous fiber reinforced thermoplastic (CFRTP) sheets is a promising techniqueused in the manufacture of structural components. In CFRTP forming, the effects thatfiber layout naturally have on the deformation mechanisms must be understood, andtemperature, pressure, speed, and stroke control should be optimized. This special issue consists of twelve recent, high-quality research articles related to themachining of CFRP composite materials. These articles include one review and eleventechnical papers on the topics of drilling, end milling, abrasive waterjet machining, andforming. The editors would like to express our deep appreciation to all the authors fortheir invaluable submissions and to the anonymous reviewers for their earnest efforts.Without these, this special issue could not have been published. We hope that furtherresearch on the machining of CFRP composites will make advances inspired by thisspecial issue.