...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Polymer Composites >Double-Vacuum-Bag Technology for Volatile Management in Composite Fabrication
【24h】

Double-Vacuum-Bag Technology for Volatile Management in Composite Fabrication

机译：用于复合材料制造中挥发性管理的双真空袋技术

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

A nonautoclave vacuum bag process using atmospheric pressure alone that eliminates the need for external pressure supplied normally by an autoclave or a press is an attractive method for composite fabrication. This type of process does not require large capital expenditures for tooling and processing equipment. The traditional single-vacuum-bag (SVB) process is best suited for molding epoxy matrix-based composites because of their superior flow and the absence of reaction byproducts or other volatiles. This is not the case for other classes of materials such as polyimides and phenolics. Polyimides and phenolics are cured by condensation reactions which generate water as a reaction byproduct. In addition, these materials are commonly synthesized as oligomers using solvents to facilitate processability. Volatiles (solvents and reaction byproducts) management therefore becomes a critical issue. SVB molding, without additional pressure, normally fails to yield void-free quality composites for these classes of resin systems. A double-vacuum-bag (DVB) process for volatile management in composite fabrication using common molding equipment was designed and built at the NASA Langley Research Center. This experimental DVB process affords superior volatiles management compared with the traditional SVB process. Void-free composites are consistently fabricated as measured by C-scan and optical photo-microscopy for high-performance polyimide and phenolic resins.
机译：单独使用大气压的非高压釜真空袋工艺可消除通常由高压釜或压力机提供的外部压力的需求，这是复合材料制造的一种有吸引力的方法。这种类型的过程不需要大量的资本支出用于加工和处理设备。传统的单真空袋（SVB）工艺最适用于模制基于环氧基质的复合材料，因为它们具有优异的流动性并且不存在反应副产物或其他挥发物。对于其他类别的材料（例如聚酰亚胺和酚醛树脂）则不是这种情况。聚酰亚胺和酚类化合物通过缩合反应固化，生成水作为反应副产物。另外，这些材料通常使用溶剂合成为低聚物以促进可加工性。挥发物（溶剂和反应副产物）的管理因此成为一个关键问题。在没有附加压力的情况下，SVB成型通常无法生产出用于此类树脂体系的无空隙质量的复合材料。美国国家航空航天局兰利研究中心设计并建造了一种双真空袋（DVB）工艺，用于使用通用成型设备在复合材料制造中进行挥发管理。与传统的SVB工艺相比，该实验DVB工艺提供了出色的挥发物管理。无空隙复合材料的制备始终如一，通过C扫描和光学显微镜对高性能聚酰亚胺和酚醛树脂进行测量。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号