Abstract:In this paper, adopting CF/PEKK and CF/PEEK thermoplastic composites as research objects, a preliminary comparative study were conducted between the two systems using corresponding process of low-cost hot-press molding and automated fiber placement (AFP) process. The basic characteristics, obtained composites quality and properties of two thermoplastic composites were explored and analyzed. Firstly, hot press molding process of CF/PEKK system with a prepreg width of 305mm was optimized, which showed that its short beam strength is more affected by molding pressure rather than cooling rate. A satisfactory CF/PEKK composite was fabricated using a process with molding pressure of 2.0MPa, heating temperature of 370℃, and cooling rate of –15℃/min, generating a short beam strength up to (135.65±4.72)MPa, with fiber volume fraction of 61.8%. Meanwhile, a novel two step in-situ AFP combined with hot press molding process was preliminary explored using 6.35mm width CF/PEEK narrow thermoplastic prepreg. It is found that obtained CF/PEEK laminates using same process parameters revealed satisfactory surface and internal quality and similar failure mode to that of CF/PEKK system, while showed lower short beam strength and different micro-scale failure behavior. The research results can provide basic data and technical reference for the material and process selection of thermoplastic composite used in future aviation structures.