Accession Number : ADA321149

Title :   Thermoplastic Ribbon-Ply Bonding Model.

Descriptive Note : Technical memo.,

Corporate Author : NATIONAL AERONAUTICS AND SPACE ADMINISTRATION HAMPTON VA LANGLEY RESEARCH CEN TER

Personal Author(s) : Hinkley, Jeffrey A. ; Marchello, Joseph M. ; Messier, Bernadette C.

PDF Url : ADA321149

Report Date : JAN 1996

Pagination or Media Count : 61

Abstract : With thermoplastic matrix resins, on-line consolidation of continuous-fiber composite laminates offers the potential of eliminating the post-placement autoclave or oven curing step, thereby simplifying the process and reducing costs. The aim of the present work was to identify key variables in rapid weld-bonding of thermoplastic tow (ribbon) and their relationship to matrix polymer properties and to ribbon microstructure. Theoretical models for viscosity, establishment of ply-ply contact, instantaneous (Velcro) bonding, molecular interdiffusion (healing), void growth suppression, and gap filling were reviewed and synthesized. Consideration of the theoretical bonding mechanisms and length scales and of the experimental weld/peel data allow the prediction of such quantities as the time and pressure required to achieve good contact between a ribbon and a flat substrate, the time dependence of bond strength, pressures needed to prevent void growth from dissolved moisture and conditions for filling gaps and smoothing overlaps

Descriptors :   *THERMOPLASTIC RESINS, FILAMENT WOUND CONSTRUCTION, MICROSTRUCTURE, TIME DEPENDENCE, FIBER REINFORCED COMPOSITES, DIFFUSION BONDING, MATRIX MATERIALS, VISCOSITY, PLASTIC FLOW, WELDABILITY, ADHESIVE BONDING, POLYCRYSTALLINE, PEEL STRENGTH, LAMINATED PLASTICS.

Subject Categories : Plastics

Distribution Statement : APPROVED FOR PUBLIC RELEASE