高铁用超高绝热性能夹芯碳纤维复合材料的制备及其性能研究

Preparation and Performance Study of Ultra High Insulation Performance Sandwich Carbon Fiber Composite Materials for High Speed Rail

摘要: 本文研究了一种具有超高绝热性能的电磁防护碳纤维夹芯复合材料制备方法，使用电磁屏蔽碳纤维复合材料为蒙皮，二氧化硅/聚酰亚胺气凝胶为芯材，阻燃环氧树脂为粘合剂。通过调节配方改变材料的厚度、密度、导热性能、力学性能等指标，从而获得满足性能要求的材料。以厚度为20 mm的复合材料为例，其密度约为0.15 g/cm3~0.26 g/cm3；在10 kHz~18 GHz频段，材料的电磁屏蔽效能 ≥ 40 dB，室温热导率约为0.021 W/m.k，压缩杨氏模量和屈服强度分别超过7.21 MPa和0.334 MPa，具有优异的热稳定性(可以在150℃下稳定使用)，和良好的阻燃性能(满足DIN-5510相关标准)。

Abstract: In this paper, a preparation method of electromagnetic shielding carbon fiber sandwich composite materials with ultrahigh thermal insulation performance for high speed rail is proposed. The electromagnetic shielding carbon fiber composite is used as the skin, silica/polyimide aerogel as the core, and flame-retardant epoxy resin as the adhesive. By adjusting the formula to change the thickness, density, thermal conductivity, mechanical properties and other indicators, a material that meets the performance requirements can be obtained. Taking a composite material with a thickness of 20 mm as an example, its density is approximately 0.15 g/cm3~0.26 g/cm3; in the 10 kHz~18 GHz frequency band, the electromagnetic shielding effectiveness is above 40 dB, the room temperature thermal conductivity is about 0.021 W/m.k, the compressive Young’s modulus and yield strength exceed 7.21 MPa and 0.334 MPa, respectively. It has excellent thermal stability (can be used stably at 150˚C), and good flame retardant performance (meet DIN-5510 standards).