SBIR Phase I: The Digital Spinneret

这个小型企业创新研究第一阶段项目将在提议公司伦斯勒理工学院和蒙特利尔大学已经开展的工作的基础上，确定大规模并行激光化学气相沉积(LCVD)碳化硅纤维的最佳工艺参数。陶瓷纤维通常是使用聚合物前驱体生产的，这意味着几乎不可能获得化学计量比纯纤维，这限制了它们在要求苛刻的应用中的潜在性能(通常是严重的)。我们的直接化学气相沉积生产纯纤维的方法在单一的“挤出微管”中生产高纯度的单丝，但商业放大需要制造方法的巨大变化。第一阶段的研究将研究创造一种同时生长许多纤维的“数字喷丝板”(DS)所涉及的参数。DS方法提供了微管中的纤维稳定性和生长条件，使其有机会一次生长数百或数千根纯纤维。通过创建DS试验台平台，第一阶段研究将确定在DS上生长此类纤维的条件，包括前体气体混合物、激光功率和几何形状以及纤维几何形状，同时还将为大规模并行化的工程路径提供输入。该项目的广泛影响/商业潜力相当大，因为它直接关系到高纯度陶瓷纤维的规模化生产。虽然近期的重点是用于涡轮机械的碳化硅纤维，但开发的技术将适用于任何标准CVD成功的材料的纤维，如装甲和高强度/重量结构中的硼和碳化硼，用于工具/磨损的碳化钨，以及用于超导线材的二硼化镁。高性能纤维的市场包括军事和航空航天(涡轮机械、火箭、先进结构)、汽车、生物医学、能源和其他行业，这些行业需要具有特殊强度、硬度、耐热性和/或耐化学性的先进材料。这些都是增长迅速、潜力巨大的光纤市场，总规模超过10亿美元。并行LCVD的能量消耗是竞争方法的1/1000，因为能量只在需要的地方使用--在光纤生长区域--并且前体浪费也被降到最低。与标准生产方法相比，这提供了巨大的成本和环境优势。这种平台技术在很大程度上与材料无关，将开发成本与特定材料脱钩。最后，规模化高性能纤维产能的成功开发解决了国内供应问题，这是一个相当受国家关注的问题。

This Small Business Innovation Research Phase I project will determine optimal process parameters for massively parallel Laser Chemical Vapor Deposition (LCVD) of silicon carbide fibers by building on work already performed at the proposing company, Rensselaer Polytechnic Institute, and the University of Montreal. Ceramic fibers are typically produced using polymeric precursors, which means that stoichiometrically pure fibers are almost impossible to attain, limiting (usually severely) their potential performance in the demanding applications they are intended for. Our direct LCVD production method for pure fibers produces high purity monofilaments in a single "extrusion microtube", but commercial scale-up requires a sea change in manufacturing approach. Phase I research will investigate the parameters involved in creating a "Digital Spinneret" (DS) that grows many fibers at once. The DS approach provides the fiber stability and growth conditions found in microtubes with the opportunity to grow hundreds or thousands of pure fibers at a time. By creating a DS test bed platform, the Phase I research will identify the conditions under which such fibers may be grown on a DS, including precursor gas mixtures, laser power and geometry, and fiber geometry, while also providing inputs to an engineering path toward massive parallelization. The broader impact/commercial potential of this project is quite large, as it bears directly on scaled production of high purity ceramic fibers. While the near-term focus is on SiC fibers for turbo machinery, the technology developed will be applicable to fibers of any material where standard CVD has been successful, such as boron and boron carbide in armor and high strength-to-weight structures, tungsten carbide for tooling/ wear, and magnesium diboride for superconducting wires. The markets for high performance fibers include military and aerospace (turbo machinery, rockets, advanced structures), automobile, biomedical, energy, and other industries that require advanced materials with exceptional strength, stiffness, heat resistance and/or chemical resistance. These are fast-growing fiber markets with great potential, the collective size of which exceeds $1 billion. The energy footprint of parallelized LCVD is 1/1000th that of competing methods because energy is only used where needed - in the fiber growth region - and precursor waste is minimized as well. This provides huge cost and environmental advantages over standard production methods. This platform technology is largely material-agnostic, decoupling development costs from specific materials. Finally, successful development of high-performance-fiber capacity at scale solves the problem of domestic supply, an issue of considerable national concern.