SBIR Phase I: High-Efficiency Closed-System Chemical Vapor Infiltration (CVI) Process

这个小型企业创新研究（SBIR）第一阶段项目将展示一种新型的、高效的纤维预成型渗透/致密化工艺的可行性。这种方法被称为封闭系统化学蒸汽渗透（CSCVI），与传统的CVI相比，具有几个优点。原料的高效利用，未反应的原料很容易回收，以备将来使用，从而最大限度地降低材料成本。因为这个过程是在一个密封的系统内进行的，所以没有废物流，只有极少量的有害物质被使用。废物流的急剧减少意味着废物处理成本的大大降低。该项目将专门研究纤维增强陶瓷基复合材料（cmc）的制造。通过高效运行和最大限度地减少废物流，预计每个部件的成本将降低约45%，仅基于材料成本。此外，由于废物流减少了数量级，废物处理所需的资本设备将大大减少。从本质上讲，任何目前使用常规CVI的系统都可以从CSCVI的应用中受益。CSCVI的成功演示有望提高陶瓷基复合材料的经济性。碳/碳化硅（C/SiC）和SiC/SiC材料的成功使cmc受益匪浅。然而，这些材料的成本相当高，任何将显著降低其成本的技术都有望找到一个巨大的商业市场。

This Small Business Innovation Research (SBIR) Phase I project will demonstrate the feasibility of a novel, high-efficiency process for the infiltration/densification of fiber preforms. This method, designated closed-system chemical vapor infiltration (CSCVI), offers several advantages over conventional CVI. Raw material is used in a highly efficient manner, and unreacted raw material is easily recycled for future use, thereby minimizing materials costs. Because the process takes place inside a sealed system, there is no waste stream, and only extremely small amounts of hazardous material are used. The dramatic reduction in the waste stream translates into greatly reduced costs for waste treatment. This project will specifically address the manufacture of fiber-reinforced ceramic matrix composites (CMCs). By operating at high efficiencies and minimizing the waste stream, it is expected that the cost reduction per part will be about 45%, based on material costs alone. Furthermore, because the waste stream is reduced by orders of magnitude, capital equipment required for waste treatment will be greatly reduced. Essentially any system currently utilizing conventional CVI can benefit from the application of CSCVI. A successful demonstration of CSCVI is expected to improve the economics of ceramic matrix composites. CMCs have benefitted from the success of carbon/silicon carbide (C/SiC) and SiC/SiC materials. The cost of these materials is quite high, however, and any technique that will significantly reduce their cost is expected to find a large commercial market.