Effects of the Processing Parameters During Laser-Assisted On-Line Consolidation on the Thermal Properties of PEEK-Composites

Processing of high-quality thermoplastic composite parts by laser-assisted tape consolidation involves melting and solidification of the thermoplastic matrix material. The properties of the parts depend strongly on the processing parameters such as laser power, offset and anglular tilt of the laser beam. The effects of these parameters on the thermal properties (such as melting and cold crystallization point) of the processed parts are studied using a Differential Scanning Calorimeter. Furthermore, the influence of the processing conditions on the crystallinity of the matrix is investigated. The observed material APC-2 tape (PEEK-matrix) exhibits a decrease of melt and cold crystallization temperature for increasing laser powers where the latter is more pronounced. The analysis of the crystallinity data showed wide variations. It is assumed that these were caused by the assumption of uniform fiber distribution throughout the DSC-Sample. Therefore, some techniques for the determination of the actual fiber volume fraction of the samples are presented and will be investigated in future work.