SBIR Phase I: Processing of Low-Permeability Polymer Insulating Foam for Use in Extreme Temperature Applications

小型企业创新研究(SBIR)第一阶段项目寻求开发一种焊接技术，用于在应用复合包裹之前连接低渗透聚合物绝缘(LPPI)泡沫。这种复合泡沫在广泛的工作温度范围内都是灵活的，并提供了热保护、低氢渗透性和抗压强度的有用组合。所提出的原位焊接工艺的主要步骤包括：(I)使用预成型的未固化LPPI带材作为原料，(Ii)开发预成型LPPI薄板之间的锥形接头的预热手段，(Iii)开发预热LPPI原料的手段和方法，以及(Iv)开发熔化和固化LPPI焊缝的手段和方法。这项拟议的技术将使制造用于氢储存和航空航天应用的大型低温储罐成为可能。此外，由于从低温到高温的热循环，该技术有可能减少复合材料中的微裂纹。

The Small Business Innovation Research (SBIR) Phase I project seeks to develop a welding technology for joining low permeability polymer insulation (LPPI) foams prior to applying a composite overwrap. The syntactic foam is flexible over a wide range of operating temperatures, and provides a useful combination of thermal protection, low hydrogen permeability, and compressive strength. The major steps for the proposed in-situ welding process consist of (i) using pre-formed strips of uncured LPPI as feedstock, (ii) developing the means for preheating the tapered joint between the pre-molded LPPI sheets, (iii) developing the means and method for preheating the LPPI feedstock, and (iv) developing the means and method for melting and curing the LPPI weld. The proposed technology will enable the fabrication of large-scale cryogenic tanks for hydrogen storage and aerospace applications. In addition, the technology has the potential to reduce microcracks in the composite due to thermal cycling from cryogenic to elevated temperatures.