![]() To reduce the labor cost due to the manual lay-up, automated tape placement (ATP) is widely considered ( Khan et al., 2010 Comer et al., 2015 Stokes-Griffin and Compston, 2016a, b). ![]() In general, the price of those materials is very high. ![]() Moreover, a critical drawback in the use of such materials is the high manufacturing cost. and other authors ( Hsiao et al., 1991 Krishnaswamy and Kalika, 1996 Choupin, 2017 Tadini et al., 2017 Choupin et al., 2018 Li and Strachan, 2019). Only a small number of articles about the degradation and isothermal crystallization of PEKK have been published by Choupin et al. In spite of its advantages, the data on the carbon/PEKK consolidation is seldom found in the literature, however, whereas the characterization of carbon/PEEK prepreg systems has been extensively reported ( Blundell et al., 1989 Yang and Colton, 1995 Phillips et al., 1997 Ageorges et al., 1998 Gao and Kim, 2000, 2001 Wang et al., 2001 Stokes-Griffin and Compston, 2016a Talbott et al., 2016). PEKK has a higher glass transition temperature (155☌) than PEEK (145☌) and offers a better high temperature resistance, whereas it has a similar melting temperature (335–340☌) which leads to almost the same manufacturing condition as PEEK. Recently, more attention is being paid to Poly-Ether-Ketone-Ketone (PEKK) as a promising matrix material for carbon fiber reinforced composites ( Chang, 1988). For example, unidirectional carbon fiber reinforced Poly-Ether-Ether-Ketone (PEEK) prepreg is a representative thermoplastic composite material used in the aircraft design ( Bishop, 1985 Carlile et al., 1989 Denault and Dumouchel, 1998 El Kadi and Denault, 2001). Among a wide spectrum of thermoplastic matrices for high performance composites are Poly-Aryl-Ether-Ketone (PAEK) matrices which have attracted great attention owing to high environmental resistance at elevated temperature. In the aircraft design and manufacturing, thermoplastic composites have many technical advantages over carbon/epoxy composites, such as high impact resistance, a short process cycle time, favorable storage conditions, and ease of patch repair. The assumption on the intimate contact establishment at the glass transition temperature was confirmed by the heat transfer simulation considering the change of thermal contact resistance at the interlaminar interface. ![]() In particular, we identified two major phenomena, the establishment of intimate contact between the adjacent layers at the glass transition temperature and the molten matrix flow at the melting temperature. To better understand the interlaminar consolidation phenomena, we developed an experimental set-up for the in-situ monitoring of the laminate consolidation to measure the change of laminate thickness and the temperature gradient in the thickness direction during the manufacturing process. This work underlined the possibility to obtain a good interlaminar consolidation quality, i.e., interlaminar shear strength of 100 MPa under a low pressure of 7.0 × 10 4 Pa even for prepregs which were not designed for out-of-autoclave processes. The quality of laminate was evaluated in terms of the interlaminar shear strength measured by short-beam shear test and the residual voids observed by micrographic images. The main objectives of this article were to examine the feasibility of high quality laminate (carbon PEKK-Poly-Ether-Ketone-Ketone) manufacturing under low pressure and to analyze the principal phenomena governing the consolidation quality.
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