The characterization and modeling of advanced thermoplastic composite material forming processes
Abstract
The objective of this research is to provide a complete understanding of typical forming processes used with advanced thermoplastic composite materials. To illustrate the methodology, the AS4/PEEK material system and a matched die molding system are used. Since the ability of the plies within a laminate to move relative to one another is vital in avoiding ply wrinkling due to compressive stresses induced by the forming process, the interply slip behavior is examined and modeled. This model is then incorporated into a forming model which takes advantage of the inclusion of transverse shear terms in the Mindlin plate theory. The transverse shear components are used to account for interply slip. A laminate subjected to a typical forming temperature, three point bend loading, and a constant forming rate is used to verify the load history predicted by the model. To analyze more complex problems, the forming model is incorporated into a finite element analysis. The matched die molding system is used to further illustrate the effects forming parameters such as temperature and rate have on the formed part. Finally, examples which demonstrate how the finite element simulation may be used to study a particular process and thus eliminate trial and error processes are presented.
Degree
Ph.D.
Advisors
Sun, Purdue University.
Subject Area
Aerospace materials
Off-Campus Purdue Users:
To access this dissertation, please log in to our
proxy server.