SUMMARY

The focus of the research is to explore the potential of using carbon fiber (CF) prepreg trim waste to manufacture lightweight, high performance and low-cost CF sheet molding compound (SMC) composites. The prepreg trim waste is available in form of tapes rolled in spools. The width of the tape and the length at which the tape is cut in the SMC are two variables which were optimized in this study. In addition, the effect of the age of the prepreg tape on the properties of the composites was determined by using “fresh” tape, which has been properly stored, and “dry” tape which has been aged at ambient conditions. The prepreg tapes are converted to SMC using a standard SMC line. Two or three SMC sheets are stacked in a mold and are compression molded into plates. The temperature and pressure profile during compression molding that resulted in the highest degree of cure of the resin in the prepreg and the smaller void content respectively were determined. Finally, the charge size and mass were varied to optimize the flow of the charge and its ability to fully fill the mold. The mechanical properties of the composites including tensile modulus and strength and impact strength were determined, according to the corresponding ASTM standards, as a function of the conditions used to make the composites and the location of the testing coupon within the plate. In addition, the density and void content were also determined experimentally. The major conclusion is that there is no need to properly store the prepreg trim waste as the performance of the composites does vary much with the age of the prepregs.