Innovative Out-Of-Autoclave composite manufacturing method for saving cost (Innovative OOA)

Important results from the project

For manufacturing of composites, Out-Of-Autoclave (OOA) manufacturing technology represents a great cost saving opportunity by eliminating the purchasing and service costs associated with autoclaves. Nevertheless, the reduction of pressure compared with an autoclave makes it difficult to achieve proper quality related to porosity. New prepregs were developed to be used with OOA. However, the use of new materials is expensive. In this study, an innovative OOA method was developed which does not require the use of a special designed OOA material.

Expected long term effects

The new innovative OOA method reduces the void content effectively and mechanically showed characteristics comparable to a conventional laminate. The method is preferably used to reduce manufacturing cost; or for larger laminates that will not fit into an existing autoclave; or as a method where an autoclave is not available. Startup companies would be specially helped from this method, due to its lower investments.

Approach and implementation

By using a thin air evacuation layer between the plies of conventional prepreg the void content was signiftcantly reduced. C-scan and microscopy were used to measure the voids content. Interlaminar shear stress (ILSS) tests were used to investigate the effect on mechanical properties. The ILSS tests show promising results, comparable to the reference laminate, suggesting that the addition of the thin air evacuation layer does not have any detrimental effects.