Effect of (0/90) and (+45/-45) plies position on the failure modes and acoustic signals in carbon fiber reinforced polymer laminates under quasi-static tensile loading

This experimental work investigates the effect of (0 degrees/90 degrees) and (+45 degrees/-45 degrees) plies position on failure modes and acoustic signals in carbon fiber reinforced polymer (CFRP) laminates under quasi-static tensile loading. Five stacking sequences, namely [(0 degrees/90 degrees)2/(+/- 45 degrees)2]S, [(0 degrees/90 degrees)/(+/- 45 degrees)/(0 degrees/90 degrees)/(+/- 45 degrees)]S, [(0 degrees/90 degrees)/(+/- 45 degrees)2/(0 degrees/90 degrees)]S, [(+/- 45 degrees)/(0 degrees/90 degrees)/(+/- 45 degrees)/(0 degrees/90 degrees)]S, and [(+/- 45 degrees)2/(0 degrees/90 degrees)2]S are fabricated by vacuum bagging process. Digital image correlation technique is used to establish strain and displacement fields in CFRP laminates during the tensile loading. Additionally, in situ acoustic sounds produced during specimen failure under tensile testing are correlated to crack formation. Finally, the two-parameter Weibull statistical analysis is employed to assess the reliability and repeatability of the experimental data.