Elevated Strain Rate Characterization of Compression Molded Direct/In-Line Compounded Carbon Fibre/Polyamide 66 Long Fibre Thermoplastic

Abstract

Compression molded direct compounded carbon fibre D-LFT was evaluated at quasi-static strain rates through uniaxial tension tests (including a specimen size study) and a variation of the ISO 6603-2 puncture test. No significant size effects were observed for the modulus or strength obtained from tensile specimens with four gauge lengths (6.25 mm to 57 mm). Failure strain decreased by 27.5%/29.9%, respectively, across the gauge length range for the 0°/90° directions. Intermediate strain rate (10 s−1 to 200 s−1) characterization was completed through uniaxial tension tests on a novel apparatus and ISO 6603-2 puncture tests. Intermediate rate tensile tests showed minimal rate sensitivity for the 0°/90° directions. Initial stiffness was 50% higher for ISO 6603-2 impact tests compared to quasi-static tests. Displacement at the onset of fracture was 95% lower for impact tests compared to quasi-static loading. The peak force/displacement at peak force were reduced for impact tests (21% and 20%, respectively) compared to quasi-static testing.