This study reports a vacuum-assisted resin infusion method for achieving low-porosity carbon fibre/phenolic resin composites utilizing a low-viscosity (∼281 cp) phenolic resin enhanced by ZrO nanoparticles. The experimental results reveal that this method can yield composites with a low porosity of 8.6 ± 2.5 % and average pore size of 3.8 ± 1.73 μm, demonstrating mechanical properties that show great potential for high-temperature structural applications, such as rocket motor nozzles. Moreover, the resultant composites exhibit distinct advantages over composites produced using other out-of-autoclave and autoclave methods investigated in this study in terms of flexural strength and modulus after oxidation treatment. The vacuum infusion approach retains higher resin content in composites than the autoclave method, leading to increased residual modulus post-oxidation. Furthermore, incorporating ZrO nanoparticles in the phenolic matrix has significantly enhanced the residual mass, flexural strength, and flexural modulus of the composites following exposure to oxidation at 1200 °C.

中文翻译：

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高压釜外真空灌注 ZrO2 纳米粒子增强碳纤维增强酚醛复合材料的抗氧化性

本研究报告了一种真空辅助树脂灌注方法，利用由 ZrO 纳米粒子增强的低粘度 (~281 cp) 酚醛树脂来实现低孔隙率碳纤维/酚醛树脂复合材料。实验结果表明，该方法可以生产出孔隙率为8.6±2.5%、平均孔径为3.8±1.73μm的复合材料，其机械性能在高温结构应用（例如火箭发动机喷嘴）中显示出巨大的潜力。此外，与本研究中使用其他非热压罐和热压罐方法生产的复合材料相比，所得复合材料在氧化处理后的弯曲强度和模量方面表现出明显的优势。与高压釜方法相比，真空灌注方法在复合材料中保留了更高的树脂含量，从而导致氧化后残余模量增加。此外，在酚醛基体中掺入 ZrO 纳米粒子显着提高了复合材料在 1200 °C 下氧化后的残余质量、弯曲强度和弯曲模量。