In this study, the fire‐retardant performance of lightweight sandwich composites, with modified epoxy impregnated carbon and glass fabric reinforcements and an aluminum honeycomb core, is investigated. The fire‐retardant performance of the fabricated sandwich composites is improved by treating carbon fiber reinforcements with phosphoric acid, and by impregnating the epoxy matrix with different loadings of ammonium polyphosphate (APP) fire‐retardant additive. The laboratory aging behavior of sandwich composites is also carried out to further investigate the degradation resistance of the panels under extreme conditions. Fire and mechanical properties of epoxy and sandwich panels are investigated using UL‐94, limiting oxygen index (LOI), thermal gravimetric analysis, compression tests, and three‐point bending tests. In the case of sandwich composites, a maximum of 1345 and 45.2 MPa flexural and compression modulus, respectively, are achieved with 10 wt% APP content in epoxy. Maximum 30% and 33% LOI values are achieved with 10% APP content in the epoxy and sandwich panels, respectively.

中文翻译：

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用于结构的阻燃碳/玻璃纤维增​​强环氧夹心复合材料

在这项研究中，研究了轻质夹芯复合材料的阻燃性能，该复合材料具有改性的环氧浸渍碳纤维和玻璃纤维增​​强材料以及铝蜂窝芯。通过用磷酸处理碳纤维增强材料，以及用不同负载量的聚磷酸铵（APP）阻燃添加剂浸渍环氧基质，可以改善人造三明治复合材料的阻燃性能。还进行了三明治复合材料的实验室老化行为，以进一步研究面板在极端条件下的抗降解性。使用UL‐94，极限氧指数（LOI），热重分析，压缩测试和三点弯曲测试研究了环氧和夹芯板的防火和机械性能。对于三明治复合材料，在环氧树脂中添加10 wt％的APP时，最大挠曲模量和压缩模量分别达到1345和45.2 MPa。在环氧树脂和夹心板上，APP含量分别为10％时，最大LOI值达到30％和33％。