PEEK OR PEKK

Which is more suitable for in-situ consolidation (ISC-in-situ consolidation) of thermoplastic composite (TPC) tapes for the production of major aircraft structures, polyether ether ketone (PEEK) or polyether ketone ketone (PEKK)? This sidebar describes the PEEK vs. PEKK debate as part of a larger discussion about whether ISC, as a true one-step, out-of-the-ocean-of-a-hot-press (OOA) process, will be able to meet the cost and productivity goals of future aircraft production (i.e., 60-70 aircraft per month for the new single-aisle jetliner, the A320). The alternative is to use a two-step process: lay-up of thermoplastic composite strips by automated fibre placement (AFP), followed by consolidation in a hot press tank or hot press machine
'For the press moulding process, both PEEK and PEKK are excellent,' says Arnt Offringa, Head of Aerostructures R&D at GKN Aerospace Fokker. . 'For the hot press tank process, PEKK is preferred because of the lower melt temperature and more robust process.'