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

这个小型企业创新研究第一阶段项目满足了对更具成本效益、碳/碳(C/C)复合材料的需求，这些复合材料具有更好的性能。将研究微波处理以提高C/C复合材料的致密化，传统上C/C复合材料是通过冗长的化学气相渗透(CVI)工艺生产的，众所周知，CVI工艺非常昂贵。创新之处在于利用微波处理在单个部件内产生温度梯度，这样就可以从内到外优先致密化，从而减少致密化时间并潜在地改善材料性能。材料焦点公司开发了一项技术，使导电碳纤维能够在碳氢化合物环境中的低压下进行微波加热，而不会产生电弧，从而导致烟尘沉积和优先加热。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，以显著缩短CVI时间。将对复合材料进行致密化和表征，以评估致密化的进展，测量强度，并提供对传统CVI加工技术的成本效益的评估。预计致密化时间将显著缩短，而不会对C/C复合材料的性能造成不利影响。高比强度C/C复合材料已在高科技应用中使用了数十年。开发低成本、高强度的C/C复合材料将使许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、火箭喷嘴和燃气轮机发动机部件。随着碳和石墨纤维的成本不断攀升，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工艺比传统CVI工艺更好，因为它有可能显着减少加工时间，从而大幅降低制造加工成本和改善复合材料性能。微波处理对社会的另一个好处是它对环境友好，通常会节省能源。科学价值将产生于更好地了解微波与不同材料的相互作用，以及微波设备设计如何对高电导率材料的加热至关重要。该奖项由2009年美国复苏和再投资法案(公共法律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).