Influence of temperature on a carbon-fibre epoxy composite subjected to static and fatigue loading under mode-I delamination

In this paper, interlaminar crack initiation and propagation under mode-I with static and fatigue loading of a composite material are experimentally assessed for different test temperatures. The material under study is made of a 3501-6 epoxy matrix reinforced with AS4 unidirectional carbon fibres, with a symmetric laminate configuration [0 degrees](16/5). In the experimental programme, DCB specimens were tested under static and fatigue loading. Based on the results obtained from static tests, fatigue tests were programmed to analyse the mode-1 fatigue behaviour, so the necessary number of cycles was calculated for initiation and propagation of the crack at the different temperatures. G-N curves were determined under fatigue loading, N being the number of cycles at which delamination begins for a given energy release rate. G(ICmax)-a, a-N and da/dN-a curves were also determined for different G(cr) rates (90%, 85%, 75%, etc.) and different test temperatures: 90 degrees C, 50 degrees C, 20 degrees C, 0 degrees C, -30 degrees C and -60 degrees C. (C) 2012 Elsevier Ltd. All rights reserved.