On the Dynamic Tensile Behaviour of Thermoplastic Composite Carbon/Polyamide 6.6 Using Split Hopkinson Pressure Bar

Abstract

A dynamic tensile experiment was performed on a rectangular specimen of a non-crimp fabric (NCF) thermoplastic composite T700 carbon/polyamide 6.6 specimens using a split Hopkinson pressure (Kolsky) bar (SHPB). The experiment successfully provided useful information on the strain-rate sensitivity of the NCF carbon/thermoplastic material system. The average tensile strength at three varying strain rates: 700, 1400, and 2100/s was calculated and compared to the tensile strength measured from a standardized (quasi-static) procedure. The increase in tensile strength was found to be 3.5, 24.2, and 45.1% at 700, 1400, and 2100/s strain rate, respectively. The experimental findings were used as input parameters for the numerical model developed using a commercial finite element (FE) explicit solver LS-DYNA®. The dynamic FE model was validated against experimental gathering and used to predict the composite system’s behavior in various engineering applications under high strain-rate loading conditions. The SHPB tension test detailed in this study provided the enhanced understanding of the T700/polyamide 6.6 composite material’s behavior under different strain rates and allowed for the prediction of the material’s behavior under real-world, dynamic loading conditions, such as low-velocity and high-velocity impact.

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

“…Bondy and Altenhof [22] carried out an LVI test on 600 mm × 600 mm CFRTP (carbon/PA6.6) panels using a 60 kg carriage and a 20 mm impactor with a mean impact velocity of 4.4 m/s, which resulted in an impact energy of 570 J. Strain-rate sensitivity was also reported on the carbon/PA6.6 material system [22]-550% higher stiffness was observed in LVI versus quasi-static loading. This supported the claim made by Mohsin et al [23] for virtually identical CFRTP system. However, the studies reported in [21,22] are not directly applicable to the automotive or aerospace industry as the impactor mass is too high and the impact velocity is too low (despite the high impact energy).…”

“…The raw materials were supplied by THERMOCOMP project [6] partners. The T700/PA6.6 material system has also previously been reported and discussed in Mohsin et al [23].…”

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 ].…”

High Strain Rate Yielding of Additive Manufacturing Inconel 625 by Selective Laser Melting

“…Once the strain rate is beyond this value, a higher slope of the rate sensitivity is shown. Note that, as the test points of the dynamic compression and tensile loading at the ambient temperature are close, the material can be approximately treated as “isotropic”, and one single bi-linear fitting is there given for ambient temperature tests [ 27 , 28 ].…”