SBIR Phase I: Lower Cost Carbon-Carbon Composites Densified by Microwave Heating

该小型企业创新研究第一阶段项目解决了对具有更高性能的更具成本效益的碳/碳（C/C）复合材料的需求。 将研究微波处理来增强传统上通过漫长的化学气相渗透（CVI）工艺生产的C/C复合材料的致密化，众所周知，该工艺成本非常高。创新是利用微波处理在单个组件内产生温度梯度，使得可以优先从内到外致密化，从而减少致密化时间并潜在地改善材料性能。 Materials Focus开发了一种技术，可以在碳氢化合物环境中的低压下对导电碳纤维进行微波加热，而不会产生电弧，从而导致烟灰沉积和优先加热。该计划将继续这项研究，以实现最佳的微波设备设计/设置，并优化工艺参数，以证明显着缩短CVI时间。复合材料将被致密化和表征，以评估致密化的进展，测量强度，并提供相对于传统CVI加工技术的成本效益评估。高比强度C/C复合材料在高科技领域的应用已有几十年的历史。 低成本、高强度C/C复合材料的开发将使众多需要高性能摩擦部件的行业以及国防所需的航空航天和国防应用成为可能。 这包括飞机刹车、离合器片、火箭喷嘴和燃气涡轮机发动机部件。 随着碳和石墨纤维的成本不断上升，需要更低成本的加工技术来使这些材料更具成本效益。 微波CVI工艺优于常规CVI，因为它具有显著减少加工时间的潜力，这可能导致显著的制造加工成本降低和改善复合材料性能。微波处理对社会的另一个好处是它是环境友好的，通常会节省能源。该奖项的科学价值将来自于对微波与不同材料相互作用的更好理解，以及微波设备设计对加热高电导率材料的关键作用。该奖项由2009年美国复苏和再投资法案（公法111-5）资助。

This Small Business Innovation Research Phase I project addresses the need for more cost effective, carbon/carbon (C/C) composites with improved properties. Microwave processing will be investigated to enhance densification of C/C composites traditionally produced by lengthy chemical vapor infiltration (CVI) processes that are known to be very costly. The innovation is to utilize microwave processing to produce temperature gradients within individual components, such that it will be possible to preferentially densify from the inside-out thus reducing densification times and potentially improving material properties. Materials Focus has developed technology that enables microwave heating of electrically conductive carbon fiber performs at low pressures in hydrocarbon environments without arcing that results in sooting and preferential heating at the soot deposits. This program will continue this research to achieve the best microwave equipment design/setup and to optimize processing parameters to demonstrate significantly shorter CVI times. Composites will be densified and characterized to assess progression of densification, measure strength, and provide an evaluation of the cost benefits over traditional CVI processing techniques. It is anticipated that densification times will be significantly reduced without detrimentally affecting the properties of the C/C composites.High specific strength C/C composites have been used for decades in high technology applications. The development of lower cost, higher strength C/C composites would be enabling to a multitude of industries requiring high performance friction components as well as aerospace and defense applications necessary for national defense. This includes aircraft brakes, clutch plates, rocket nozzles, and gas turbine engine components. As the cost of carbon and graphite fibers is escalating, lower cost processing techniques are required to make these materials more cost effective. The microwave CVI process is better than conventional CVI since it has potential to significantly reduce processing times which could result in substantial manufacturing processing cost reductions and improved composite properties. An additional benefit of microwave processing to society is that it is environmentally friendly and typically results in energy savings. The scientific value will arise from improved understanding of the interaction of microwaves with different materials and how microwave equipment design is critical for the heating of high electrical conductivity materials.This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).