Experimental and Numerical Analysis of Low-Velocity Impact of Carbon Fibre-Based Non-Crimp Fabric Reinforced Thermoplastic Composites

Abstract

There has been a lot of interest in understanding the low-velocity impact (LVI) response of thermoplastic composites. However, little research has focussed on studying the impact behaviour of non-crimp fabric (NCF)-based fibre reinforced thermoplastic composites. The purpose of this study was to evaluate the LVI responses of two types of non-crimp fabric (NCF) carbon fibre reinforced thermoplastic laminated composites that have been considered attractive in the automotive and aerospace industry: (i) T700/polyamide 6.6 (PA6.6) and (ii) T700/polyphenylene sulphide (PPS). Each carbon/thermoplastic type was impacted at three different energy levels (40, 100 and 160 J), which were determined to achieve three degrees of penetrability, i.e., no penetration, partial penetration and full penetration, respectively. Two distinct non-destructive evaluation (NDE) techniques ((i) ultrasonic C-scanning and (ii) X-ray tomography) were used to assess the extent of damage after impact. The laminated composite plates were subjected to an out-of-plane, localised impact using an INSTRON® drop-weight tower with a hemispherical impactor measuring 16 mm in diameter. The time histories of force, deflection and velocity are reported and discussed. A nonlinear finite element model of the LVI phenomenon was developed using a finite element (FE) solver LS-DYNA® and validated against the experimental observations. The extent of damage observed and level of impact energy absorption calculated on both the experiment and FE analysis are compared and discussed.

Delamination of Novel Carbon Fibre-Based Non-Crimp Fabric-Reinforced Thermoplastic Composites in Mode I: Experimental and Fractographic Analysis

“…These materials were supplied by partners in the THERMOCOMP project [ 29 ]. The T700/PA6.6 material system has also previously been reported and discussed in Mohsin et al [ 24 , 32 ].…”

“…One of the most useful real-world applications of composites is low-velocity impact, as laminated composites have been proven to be capable of absorbing higher impact energy compared to conventional metals and metal alloys [ 24 , 25 ]. Mohsin et al [ 24 ] have proven that thermoplastic composites are superior to most thermosetting composites.…”

“…One of the most useful real-world applications of composites is low-velocity impact, as laminated composites have been proven to be capable of absorbing higher impact energy compared to conventional metals and metal alloys [ 24 , 25 ]. Mohsin et al [ 24 ] have proven that thermoplastic composites are superior to most thermosetting composites. As the delamination of composite structures can be induced by the impact of low velocity, it is one of the major challenges that draws the most attention from a safety perspective.…”

Assessing Crimp of Fibres in Random Networks with 3D Imaging

“…X-ray μCT systems are used to observe fibrous composites to evaluate damage after impact. Composites made with non-crimped, carbon-fibre-reinforced thermoplastic laminations were subjected to an impact force provided by a hemispherical impactor with a 16 mm diameter, and the resulting damage was observed using an X-ray μCT system [ 8 ].…”

A Numerical Study on the Influence of Strain Rate in Finite-Discrete Element Simulation of the Perforation Behaviour of Woven Composites

“…Mohsin et al [ 9 ] performed a numerical and experimental study on the low-velocity impact response of non-crimp fabric-based composites and reported rebounding, penetration, or perforation of the impactor as possible outcomes. Matrix cracking, delamination, fibre matrix debonding, and fibre fracture were identified as probable failure modes at different stages of the laminate response.…”