Innovative preform design exploiting automated fibre placement

Advanced composite materials generally have good in-plane mechanical properties; but they struggle to perform well in the through thickness direction as this is a resin dominated loading direction. In recent years this issue has been challenged by the use of through thickness reinforcement, in the form of tufting, Z-pining, or 3D weaving; to create a laminate with superior through thickness performance. Despite these methods being effective in increasing the through thickness performance, they are not without drawbacks, such as a decrease in the in-plane performance or requiring additional manufacturing steps. This paper seeks to resolve these issues, by exploring a novel preforming method that creates a pseudo woven structure in a single preforming step using the capabilities of Automated Fibre Placement, such that in-plane properties are retained and through thickness properties are enhanced; and validated by mechanical testing of samples to the appropriate ASTM standards.