Superior fatigue stressed chassis components

The transport sector meets increasing environmental requirements, and reducing the weight of vehicles is an obvious way to reduce energy consumption in the transport sector. Material substitution represents one of the main ways to save vehicle weight and reducing CO2-footprint. Substituting steel with aluminium is a straightforward solution, however, to retain the same properties as the corresponding steel part with respect to e.g. strength and fatigue, the aluminium solution needs to be carefully designed. In the SUFICCS-project, a newly developed forming-method has been combined with established existing company technology as well as material competence to obtain automotive parts with the necessary properties and design. A novel production method, based on a new thermal treatment process for the extrusion billets, to produce extruded profiles with high strength has been developed. With this processing it is possible to increase the extrusion speed by 150-200% as compared to standard processed billets, and still obtain the same strength in the final product. This material has been combined with a newly developed forming method to obtain automotive parts with the necessary properties and design. Mechanical properties, including the fatigue properties of the alloy, has been tested in the project, and laboratory scale forming trials has been performed. Materials from these trials have been further investigated with respect to mechanical properties and microstructure. The first contract based on the results from this project has already awarded, and the production will start in 2024/2025.

- A novel method for producing high strength extruded profiles has been developed. The method, with the brand name HyperAl, is based on a high strength 6xxx alloy and a new thermal treatment process for the billets. - A new forming method for aluminium automotive parts with high productivity, reduced production time, energy usage and costs. The innovation will allow slimmer automotive parts and better utilization of the volume of the car. The freed volume will allow more space for other parts, such as batteries for electrical cars. - The proposed innovation will allow an overall reduction in car weight and consequently lower CO2 emission for transportation. - Better utilization of the starting material, and reduced waste (estimated to 20-30% less waste) is also a consequence of the proposed innovation. - Increased quantitative knowledge on fatigue properties. This is important input to the FEM modelling and enables improved design process for automotive parts.

The transport section is under constant pressure to produce innovative lightweight solutions that improve vehicle fuel consumption and consequently lower CO2-emissions. In the present project we aim at utilizing a recently developed forming method to be able to make chassis parts in aluminium that has a superior combination of design and mechanical properties. Concerning design, we are aiming at making leaner parts than all existing solutions on the marked today. This will enable better utilization of the volume in the car, and allow extra space for e.g. batteries. Leaner parts have not previously been proposed due to challenges concerning the mechanical properties, in particular fatigue. Until today, the somewhat bulky dimensions have been necessary to meet customer requirements on strength, ductility and fatigue. However, with our new forming technology together with alloys tailor-made for this product, we believe that we will be able to develop this innovation. As part of the development, we need to optimize the heat treatment of the formed material to obtain the desired properties. We also need to address the fatigue properties of the designed parts. The realization of the innovation requires intensive research effort from the industrial partners Neuman Raufoss Technology AS, Neuman Raufoss Development AS, TOTAL DEFENCE GROUP AS, Hydro Aluminium and AP&T. The complementary research effort from the research partners (SINTEF Industry and SINTEF Manufacturing) is essential to obtain the envisaged results.