France-Australia Technical Arrangement TA 1/99 - Work Package 1: Study of the Equivalence of Hot/Dry and Hot/Wet Testing

摘要

Substantial savings could be made in the airworthiness certification of composite aircraft structure if the strength of polymer matrix composites in the elevated temperature wet (ETW) condition could be predicted from parameter that are easier to measure such as strength in the elevated temperature dry (ETD) condition and the glass transition temperature (Tg). The feasibility of this approach was tested by measuring the strength of AS4/3501-6 unidirectional prepreg tape, T650/F584 plain weave prepreg fabric and T650/PR500 plain weave fabric consolidated by resin transfer moulding, in the dry and 70 deg C/85 % relative humidity equilibrated condition, from 25 to 120 deg C using interlaminar shear, +-45 deg tension, open hole compression and compression after impact tests. Apart from a decrease in strength with increasing temperature and moisture content there was no consistent relation between ETD and ETW strength. It was therefore not possible to predict ETW strength for these materials and tests on the basis of ETD strength and Tg only.