Processing Fundamentals and Process Modification for Rapid Liquid Molding of High-Performance Composites

高性能复合材料快速液态成型的加工基础和工艺改进

基本信息

批准号：
9522801
负责人：
Ranga Pitchumani
金额：
$ 23.45万
依托单位：
University of Connecticut
依托单位国家：
美国
项目类别：
Continuing Grant
财政年份：
1995
资助国家：
美国
起止时间：
1995-10-01 至 2000-09-30
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=9522801&HistoricalAwards=false
关键词：
Processing Fundamentals Process Modification Rapid

项目摘要

9522801 Pitchumani Liquid molding with processes like resin transfer molding, is a way to fabricate relatively high volumes of complex, high performance composite products at reasonable costs. A key to the success of liquid molding is uniform and complete filling of a closed and vented mold with resin. Because the inside of the mold is a labyrinth of composite preforms and inserts, the flow permeability is difficult to model and predict. This project uses an analytical and experimental investigation of fractals as a way to describe pore structure. This allows calculation of the permeability inside the mold. With fratal models for the tortuous length and capillary size, the permeability can be determined using Darcy's law so the flow in the closed mold can be calculated using existing numerical codes. An experimental setup to verify this approach uses a three-part Plexiglas mold, and a video and image processing system to document the flow pattern and determine the fractal dimensions of the composite mat. Passing a current through conductive fibers that are part of the preform is a process innovation that will be investigated to improve the uniformity of curing. The impact of this research will be improvements in the design of venting systems and uniform filling in liquid composite molding processes, leading to lower costs and more opportunities for use of these high performance materials. ***

9522801 Pitchumani 液体成型采用树脂传递成型等工艺，是一种以合理的成本制造相对大量复杂、高性能复合材料产品的方法。液体成型成功的关键是用树脂均匀且完全地填充封闭且通风的模具。由于模具内部是复合材料预成型件和嵌件的迷宫，因此很难对流动渗透率进行建模和预测。该项目使用分形的分析和实验研究作为描述孔隙结构的方法。这允许计算模具内部的渗透率。通过曲折长度和毛细管尺寸的分形模型，可以使用达西定律确定渗透率，因此可以使用现有的数值代码计算闭合模具中的流动。验证这种方法的实验装置使用三部分有机玻璃模具以及视频和图像处理系统来记录流动模式并确定复合垫的分形维数。让电流通过作为预成型件一部分的导电纤维是一项工艺创新，将对其进行研究以提高固化的均匀性。这项研究的影响将是改进排气系统的设计和液体复合材料成型工艺中的均匀填充，从而降低成本并增加使用这些高性能材料的机会。 ***