Researchers at Colorado State University have developed a new approach for one-step winding and curing of composite structures. This can be utilized in fabrication of axisymmetric composite structures such as pressure vessels and tanks, pipes, shafts, and wheels. This technique can be done in a fraction of time compared to traditional materials and processes.
Filament winding is one of the main manufacturing techniques for fabrication of axisymmetric composite structures. In filament winding, fiber reinforcements impregnated with resin are first wound on a rotating mandrel, after which the layup is vacuum bagged and transferred to an oven/autoclave for thermal curing of the composite materials during long cure cycles, often great than 6 hours. Alternatively, the materials can be heated and cured during or after the winding step on the rotating mandrel (without transferring to an oven/autoclave) using radiative heating or other remote heating methods. Such approaches typically require long process times due to the long cure cycles of matrix resins.
In this approach, a thermoresponsive resin system is used as the matrix resin of composites that has a long working time (> 2 hours) but can instantaneously cure and solidify in response to a thermal stimulus. The supplied heat can cure the material as it is being wound or after the winding process is complete. As a result, composite structures can be cured on the mandrel within a few minutes (1 to 15 minutes depending on the thickness of the structure) without using an oven or autoclave, thus eliminating the extra steps for bagging and long-cycle curing of composite structures.
Licensed
US Provisional Patent
Mostafa Yourdkhani