**1. Introduction**

During service, aircraft structures are subjected to dynamic loads such as impact with foreign bodies, projectile impacts, and shock waves, which may significantly affect the mechanical properties of thermoplastic fiber-reinforced (TFR) composite materials used for these high-performance structures [1–3]. Thus, a reliable design of the composite components requires a detailed mechanical characterization at high strain rates because in most cases, due to the lack of dynamic properties, static properties are used in material selection and design, which can result in excessive structural weight or cause unexplained and untimely failure [1, 4–6].

Efforts have been made to determine the relation between fiber-reinforced polymer matrix composite (FRPC) mechanical properties at high strain rates and material configuration (resin and fiber length, concentration and orientation), using different high strain rate test techniques. Different authors have report and analyzed several researches as a state of the art in this topic; however, most of the studies are focused on thermoset composites, especially epoxy and polyester matrices reinforced with glass

and carbon fibers [3, 5, 7–13]. The few works found in open literature about thermoplastic composites studied polyamide-reinforced composites (with glass and carbon fiber with different fiber configurations), ethylene-propylene copolymer (EPC) matrix reinforced with discontinuous glass fibers, commingled e-glass/polypropylene woven fabric composite, glass fiber-reinforced polypropylene (PP) and polybutene-1 (PB-1), and AS4 graphite/polyetheretherketone (PEEK) thermoplastic composite [4, 11, 14–20]; however there is a lack of information about PPS matrix composite's behavior.

Among the several techniques to achieve high strain rates for tests [21], the split-Hopkinson pressure bar testing is often used for composite materials [3, 5, 10, 18, 22–29], where both the specimen stress-time and the specimen strain-time response are calculated from the strain waves measured on the bars. Additionally, high-speed camera technology with high resolution allow to apply optical and contactless strain field measurement techniques such as digital image correlation (DIC), to obtain accurate data reduction possibilities and more information on the distribution of strain over the specimen surface, which will be later employed in the dynamic material characterization [11, 26, 30, 31]. Within this context, the present work uses these techniques to characterize the strain rate effects on the mechanical behavior of PPS matrix carbon fiber-reinforced composite under compressive loadings in both static and dynamic regimes. Results obtained from dynamic statics are compared with quasi-static test results for the same specimen geometry and batch. Images obtained by high-speed imaging are used during tests to help to identify macro-failure modes induced at high strain rate tests, while micro-failure observation was carried out to identify quasi-static failure aspects and damage mechanisms of the material at all tested strain rates.
