Application Note: TBD
CNF was dispersed into polyester. Preforms were fabricated with an aluminum foil insert along the centerline to create the notch for delamination testing. VARTM process was used for impregnation random fiberglass lamina with the CNF/resin suspension. The samples then underwent Mode-I Double Cantilever Beam (DCB) testing. The DCB test calculates the critical energy release rate in which the crack propagates perpendicular to the loads.
Top left graph: Linear curve fitting of crack length. The crack length was curve fitted to compensate for the growth between data points.
Top right graph: Load-displacement curves of DCB specimens. This plot shows that the force applied to the 1% CNF composites was higher than the 0% CNF composites.
Bottom left graph: Mode-I delamination resistance curve. The critical energy release rate in mode-I delamination was calculated and plotted against delamination crack length. This plot show that the 1 wt% CNF toughened composites have a higher resistance to mode-I delamination than the traditional polyester composite (0 wt%). The improvement in critical energy release rate is about 100%.
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