Stretchable Unidirectional Fiber Reinforcement
Abstract
Small staggered cuts were made in unidirectional prepreg to allow it to stretch. The cuts were made either just locally where required for a complex mold, or throughout the whole prepreg. Three tests were performed: uni-axial tensile tests of flat specimens, mold conformability tests to evaluate manufacturability, and manufacturing and structural tests of round tubes. The cuts reduced the tensile strength by less than 20%. The conformability tests used a complex shaped mold for part of a radome and the locally cut prepreg significantly simplified layup and reduced fiber waviness and hammocking. The tubes were made by winding prepreg on male mandrels, and then transferring the prepreg to a female mold for curing. The tubes made with stretchable prepreg were considerably less affected by mandrel size, had excellent surface finish, and within 3-6% possessed the same strength as the best tubes made with conventional prepreg.
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 09, 2009
- Accession Number
- ADA520771
Entities
People
- Joachim L. Grenestedt
Organizations
- Lehigh University