G8 Sustainable Manufacturing: Out-of-Autoclave Processing


Student: Adam W. Smith - PhD student

Supervisor: Prof. Pascal Hubert

Sponsors: NSERC

Fibre-Reinforced Polymer Recycling (Primary Research Focus)

Increased production of composite-intensive aircraft, automobiles, wind turbines, and aquatic vessels translates directly into the production of more fibre-reinforced polymer scrap entering the waste stream. There exists a demand for methods and expertise in the recycling of both manufacturing and end-of-life composite waste. To date, this demand has been met with recycling technologies such as mechanical comminution, thermal and chemical decomposition, all of which result in a drastic loss in the initial energy placed in these high value materials.
This research focuses on the development of a methodology for recovering and reusing aerospace prepreg scrap in the form of Long-Discontinuous-Fibre (LDF) composites to be processed using a compression moulding operation.

TCX Heated Tool Plate (Supporting Role)

While out-of-autoclave (OOA) prepregs have demonstrated significant promise for the production of low cost high quality parts in a vacuum-bag-only (VBO) convection oven process, high cycle times limit their application in many cases. Replacing the convection oven with a heated tool presents the opportunity for reduced cycle times and improved process control, by providing direct heating with advanced control options. The ThermoCeramix TCX™ resistive element is a novel heating technology which can be easily applied as a multilayer coating to one sided tools for prepreg manufacturing. This heating system has been shown to provide even heat distribution and a very high power density, enabling aggressive ramp rates which can help drive cycle times down. However, one-sided heating presents certain challenges which must be overcome. Namely, the process must be expanded to deal with components of varying thicknesses, and sandwich structures containing a lightweight core material. This research aims to expand the capabilities of a TCX™ heated tool to increase process flexibility and demonstrate the advantages of this method for the manufacturing of aerospace components.

Discarded carbon fibre prepreg trimmings (top-left) and expired rolls (top-right)[1] can be transformed into chips (bottom) and processed as a LDF composite via compression moulding.

[1] S. Panesar, "Converting composite waste into high quality reusable carbon fibre," JEC Composites Show. JEC Composites, Paris, France, 2009.