Acoustic emission testing of filament wound CFRP pressure vessels

초록

Acoustic emission (AE) has been applied during the proof test of filament-wound carbon-epoxy pressure vessels to help the evaluation of vessel performance and the prediction of damage accumulation. The results from coupon tests were utilized for planning the AE monitoring of hydroproof tests of pressure vessels. The filament-wound vessels were typically pressurized stepwise in six to seven steps up to 13.8MPa(2000psi), which is 1.33 times the proof pressure or about 50% of the expected burst pressure. Results of source location may provide the means to predict initial damage zone and the progressive damage accumulation. The mode of wave propagation was too complicated, however, to exactly locate the final failure. Felicity ratio was also calculated and utilized but the deviation from Kaiser effect was not so significant at this pressure level. The ratio between the number of AE events during load hold and that during pressurization appeared to be another useful index of damage accumulation.