In the study, a sample “A” pillar node was fabricated using the Bentley automated fibre deposition process, finished by pressing, and by the Sigmatex One Piece 3D weaving process with subsequent resin infusion. In this study, the technically superior composite solution was produced using the 3D woven preform and the resin infusion process. In reaching this conclusion, the study put a value of weight saving at €5/kg for this automotive application.
The study demonstrates that 3D woven preforms can be cost competitive in low volume, complex shape automotive applications. Due to the higher mechanical properties and reduced variability through automated process control, the component fabricated from 3D fabric would have a lower weight than the automated fibre placement component and a very significant improvement compared to the aluminum part.
The 3D weaving process that Sigmatex has developed differs from conventional 3D in that the throughput rates are substantially higher resulting in lower costs. This lower cost basis enabled the 3D/infusion approach to compete traditional fabrication processes such as automated fiber placement and hand layup. In production, this type of preform can be nested to reduce scrap and supplied on 100 meter rolls, with approximately 200 preforms per roll.
“The Sigmatex 3D weaving process enables complex components to be manufactured with fibres and weave architectures designed to form integral strength and stiffness. Although a little way off manufacturing a One Piece Woven Body in White, we can demonstrate that 3D woven structures can meet the technical and cost requirements for the Automotive sector.” said Chris McHugh, Technical Manager for Sigmatex.
Lee Bateup, Advanced Vehicle Technologies Specialist for Bentley commented “the programme successfully demonstrated that a 3D woven composite preform was very well suited to the very complex and highly loaded nodal structure within an automotive spaceframe. Sigmatex has made a step change in quality and cost through improved automation compared to a conventional 2D composite. The solution offers very significant weight, functionality and performance benefits compared to the incumbent aluminum component. Combined with reduced investment costs, this is a very attractive proposition for future vehicle platforms.”
Sigmatex is a leading global manufacturer of 2D woven, unidirectional, multiaxial, (non-crimp) and 3D textiles. Sigmatex uses advanced technologies to create textile solutions, which optimise the performance of carbon fibre in complex structures. Sigmatex provides products to global customers through operations in Europe, the U.S., and Asia.
About Bentley Motors
Bentley Motors is the definitive British luxury car company, dedicated to developing and crafting the world's most desirable high performance cars. Bentley Motors is the third largest R&D investor in the UK's automotive sector and the 18th largest nationally. The company employs almost 4,000 people in Crewe which is home to all its operations including design, R&D, engineering and production. The combination of fine craftsmanship, using skills that have been handed down through generations, alongside engineering expertise and cutting-edge technology is unique to UK luxury vehicle manufacturers such as Bentley. It is also an example of high-value British manufacturing at its best. Bentley exports over £500m worth of goods every year to established markets like the US, as well as emerging markets such as China and South America.
More information: www.bentleymedia.com