The originality of this paper is the study of the bending behavior of several carbon-fiber-reinforced thermoplastic sandwich composites under three-point bending tests using a mechanical-acoustic experimental coupling approach. The skins were fabricated from thermoplastic Polyphenylsulfone “PPSU” resin reinforced by 2 × 2 twill desized carbon fabrics. Different core materials (Nomex, Aluminum and Polyetherimide PEI) with different topologies (honeycomb, straight tubular and inclined tubular at 15°) and two densities (48 and 64 kg/m³) are used for the manufacturing of the different sandwich panels. During the bending tests, a laser device measured the deflection, two acoustic emission transducers evaluated the acoustic activity and a video-microscope monitored the damage evolution in-situ and in real-time. Thereby, the mechanical-acoustic coupling allowed relevant monitoring of the different strain and damage mechanisms generated within the different sandwich configurations. According to this study, the aluminum core sandwich structure presents the highest stiffness. However, the thermoplastic PEI core sandwich structures show the highest ductility and absorbed energy.

本文的独创性是使用机械声学实验耦合方法研究了几种碳纤维增强的热塑性夹芯复合材料在三点弯曲试验下的弯曲行为。表皮由热塑性聚苯砜“ PPSU”树脂制成，并用2×2斜纹脱碳碳纤维增强。具有不同拓扑结构（蜂窝状，15°的直管和倾斜管）和两种密度（48和64 kg / m ³）的不同芯材（Nomex，铝和聚醚酰亚胺PEI））用于制造不同的夹心板。在弯曲测试过程中，激光设备测量了挠度，两个声发射换能器评估了声活动，并且视频显微镜实时监测了损伤的演变。因此，机械-声耦合允许对在不同的夹心结构内产生的不同的应变和损伤机理进行相关的监测。根据这项研究，铝芯夹层结构具有最高的刚度。但是，热塑性PEI芯夹层结构具有最高的延展性和吸收的能量。