Manufacturing study of unidirectional AS4D/PEKK tape

The manufacturing characteristics of unidirectional AS4D reinforced PEKK tape has been studied with a view to using this composite system for high performance applications. The quality of components produced by two processing routes, press forming and autoclave moulding, have been compared. The first stage of the assessment focused on flat laminates manufactured by using both techniques. Mechanical property and physio-chemical analyses have been carried out on coupons extracted from these panels. The second phase of this investigation evaluated dimensional variability. A series of "L-shaped" components have been produced to determine values for spring-back and to allow radii integrity to be assessed. The same material system has been employed in the design and manufacture of 'top-hat' stringer components for aerospace applications. The results from the dimensional variability analysis outlined above were used in the tool design for the structures in order to meet stringent part tolerance and quality specifications. Mechanical, physical and non-destructive inspection testing was undertaken for process control. The resulting analysis demonstrates the repeatability and stability of measurements achieved over a 'quasi' production schedule for thermoplastic composite components.