| Abstract Scope |
Automated Fiber Placement (AFP) is the leading technology in automated layup of aerospace composite structure, offering enhanced quality, reliability, and production rates over traditional methods. Prepreg tack is a critical material property that directly impacts the process quality outcomes. During the process, tack can be managed through control of process parameters such as temperature, rate and force. A comprehensive understanding of tack and its relationship with processing conditions is crucial for the successful management of material deposition.
An AFP Simulator system (denoted as µAFP) was previously developed that simulates deposition of a single prepreg tow under controlled conditions. An in-situ peel test method has been developed, utilizing the µAFP to peel the prepreg off from the underlying substrate, directly following the tow deposition process. The resulting peel resistance of tack is characterized through in-situ measurement of tow tension during the peel-off process. The implementation of the in-situ peel test in µAFP enables researchers to study the independent effects of deposition and peel rates, deposition and peel temperatures, compaction force, and compaction roller material grade on prepreg tack. Further, tack can be characterized at rates up to 700 mm/s – significantly higher than those achievable with conventional testing methods and much more representative of AFP conditions. Here, the in-situ peel test is conducted for a variety of process parameters, and tack results compared against the existing literature (in the available range of rates). Good agreement is observed, confirming the validity of this new approach. |