New materials found across the Galaxy

Vehicle manufacturers are turning to high strength steels for their combination of structural, crash and weight benefits. Dean Palmer reports

Corus, the international steel company, has been working with Ford to help the car manufacturer implement high strength steels in the new Galaxy model range. The demand from vehicle manufacturers for high strength steels, including the latest dual-phase materials, is increasing due to their combination of structural, crash performance and weight benefits. The steels offer vehicle engineers a balance between strength and formability. However, they behave differently to traditional steel grades so require a certain amount of expertise to implement successfully. The collaborative work involved using Corus’ material expertise and computer simulation techniques to help Ford identify a number of key parts in the rear structure of the Galaxy that could benefit from high strength steels. Importantly, improved application of high strength steels during the early design and engineering phase of the new Galaxy has provided opportunities to reduce development time and costs and improve vehicle crash performance. Peter Jones, customer engineering manager at Corus Automotive, told Eureka: “There is a growing need for carmakers to understand fully how these new materials perform – both during the forming process and in-service on the vehicle – with crash performance being particular important.” Working closely with Ford engineers at Merkenich, collaborative projects undertaken by Corus on the Galaxy included forming feasibility studies on the rear floor, rear-cross member and the heel-kick panels. The study on the rear-floor panel looked at opportunities to reduce the gauge (and weight) of the panel, while ensuring that its complex shape was feasible to press. According to Jones, with the growing use of high-tech steels in automotive press shops, it is increasingly important for carmakers to fully understand how a material will deform and flow during pressing. Corus was also involved in a detailed parts integration study of the rear floor panel. “In this study, we showed that it was possible to use one part for the floor panel instead of the originally planned two – allowing Ford to save on tooling, process and manufacturing costs,” explained Jones. For the heel-kick and rear-cross member panels, Corus showed that it was possible to down-gauge in order to reduce weight, replacing high strength low alloy steels with dual-phase material, whilst retaining the same impact performance for these panels. As part of its collaborative work, Corus also used its materials analysis simulation technique, Forming to Crash or ‘F2C’ to help Ford engineers evaluate the crash performance of key parts such as the rear longitudinals made from its dual-phase material. By using computer crash analysis techniques, Ford engineers were able to optimise the design of these parts during development.