Experimental study on hole quality and its impact on tensile behavior following pure and abrasive waterjet cutting of plain woven CFRP laminates

Waterjet cutting of composites has been proven to be feasible with specific advantages compared with traditional machining techniques, while it still possesses several challenges. Experimental data is presented in this paper relating to hole quality and tensile behavior when using water jet cutting of plain woven CFRP laminates with various processing parameters. The effect of typical parameters including transverse speed, waterjet pressure, and with/without abrasive particles on surface integrity was also studied. A full factorial experimental array was employed involving eight trials. The statistical significance of individual cutting parameters was determined using ANOVA analysis. Results showed that abrasive particles played an important role in workpiece material removal process during waterjet cutting. Typical surface defects including severe entry/exit delamination, uncut fibers, and fiber burrs were observed in CFRP laminates cut by pure waterjet, while marginal damage was recorded when using abrasive waterjet with the same processing parameters. Strip marks together with various defects including craters, uncut fibers, and fiber pull-out were observed on the machined hole surface. Tensile strength of CFRP laminate with open hole cut by waterjet was significantly affected by hole quality, which was increased by up to similar to 22% (130 MPa) with sample cut by abrasive waterjet than the one processed by pure waterjet with the same cutting parameters. Massive delamination, fiber breakage, and splitting bands were the main tensile failure modes.