Abstract In this study, a novel approach to improving the fire performance of sandwich composites without effect on intrinsic composite structure was explored. The intumescent mat M10 and M20 with expansion ratio 10:1 and 20:1, respectively, were used to protect sandwich composite with evaluation for thermal insulation, heat release rate, smoke density, smoke toxicity, and post-fire performance. Due to char layer formed with expanded graphite when intumescent mat exposed to fire, significant reduction in the maximum average rate of heat emission (MARHE), specific optical density and Valeur Obscurcissement Fumee values in the initial 4 min (VOF4) were observed for sandwich composite with intumescent mat protection, which also improved mechanical properties retention following exposure to flame. According to the EN 45545 standard, all composites passed HL3 hazard level of smoke toxicity. However, due to higher expansion ratio, sandwich composites with M20 mat passed HL3 hazard level of MARHE and HL2 for specific optical density. As such, the M20 mat with excellent flame retardant performance and mechanical properties retention could be potentially used for rail industry applications.

中文翻译：

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具有膨胀垫保护的夹层复合材料的 Fie 性能：不断发展的隔热、火灾后性能和铁路行业测试

摘要 在本研究中，探索了一种在不影响复合材料固有结构的情况下提高夹层复合材料防火性能的新方法。分别采用膨胀比为10:1和20:1的膨胀垫M10和M20保护夹层复合材料，并对其隔热性、热释放率、烟雾密度、烟雾毒性和火灾后性能进行评估。由于膨胀垫暴露在火中时由膨胀石墨形成炭层，观察到夹心复合材料的最大平均热发射率 (MARHE)、比光密度和初始 4 分钟内的 Valeur Obscurcissement Fumee 值 (VOF4) 显着降低具有膨胀垫保护，这也提高了暴露于火焰后的机械性能保持率。根据 EN 45545 标准，所有复合材料均通过了烟雾毒性的 HL3 危险等级。然而，由于具有更高的膨胀比，M20 垫的夹层复合材料通过了 MARHE 和 HL2 的 HL3 危险等级，以获得特定的光密度。因此，具有优异阻燃性能和机械性能保持的 M20 垫子有可能用于铁路行业应用。