Instrumented linear cutting device for the analysis of fiber severing process

Abstract

In recent years, stringent governmental regulations along with falling carbon fiber prices have pushed high-volume composite manufacturing somewhere at the top of the “to do” list for the majority of carmakers. However, a careful survey of the literature reveals that little is available on the topic of high-throughput severing of the carbon fibers, one of the principal constituents of carbon fiber reinforced polymers. To address this relative paucity of valid scientific information, the major goal of this study was to develop a robust and accurate experimental apparatus capable of establishing correlations between the amount of cutting force developed at the blade/fiber tow/deformable backing interface and various process parameters such as fiber material, tow and backing characteristics, blade geometry/material, and so on. The characteristic cutting force–position curves obtained by means of the developed device suggest that (1) the cutting forces require to cut glass fibers are typically larger (up to 27% observed in this study), (2) softer backings tend to have a positive effect on the fiber severing process both in terms of peak cutting force and total work to cut, and (3) dull blades require either larger severing forces (60 µm blade edge radius was associated with a 21% increase in cutting force) or are simply unable to produce severing of the fibers (80 µm blade edge radius). Future extensions of this work will focus on the determination of systematic correlations between the parameters of fiber severing process.