The Taylor impact and high strain-rate response of poly(chlorotrifluoroethylene) PCTFE, poly(ether-etherketone) PEEK and Kel-F 800

The mechanical properties of PCTFE, PEEK and Kel-F 800 have been investigated over a range of temperatures using both the Taylor impact geometry and Hopkinson bars. PCTFE and PEEK are both industrially important polymers. Kel-F 800 (comprising 75wt\% PCTFE and 25wt\% poly(vinylidene fluoride) PVDF) was a 3M product that is still used as a binder material in polymer bonded explosives. Compression and tensile Hopkinson bars have been used to generate stress vs. strain data over a range of temperatures for each polymer. Additionally, quasi-static tension and compression data has been collected with respect to strain-rate and temperature for comparison. The Taylor impact geometry has been used to study the ballistic response. High-speed photography was used to quantify sample deformation as a function of time. In each material, a transition velocity is identified between a ductile plastic response involving sample bulging and a brittle response initiated by cracking. Post-shot microscopy has been undertaken to elucidate failure mechanisms.