Claude Maack introduces fully automated industrial equipment using endless wet fibres for manufacturing 3D ultra-lightweight structures
Endless fibre winding for 3D components is moving to the next level with a fully automated winding process. The process is wet winding of impregnated fibres around or on a winding mould. Various fibres can be used, including carbon (high strength or high E-modulus), glass or natural fibres such as basalt, hemp, flax, ramie or others.
The matrix used is a thermoset type. Various resins can be used as well and these are mono-component or duo-component with some additives for meeting certain specific requirements depending on their application (e.g. fire smoke and toxicity in aerospace, outgassing and extreme temperature ranges in space applications). Furthermore, the traditional polymers with hardener could be replaced in the future with biobased polymers – an area where there is still some development in front of us.
Industry applications of the wet winding process
Applying all possible fibre materials with the huge amount of polymer materials now will open a large panel of possibilities and applications. As the impregnation is realised directly on the robot (wet winding), this system is giving maximum of flexibility for multiple business fields, such as aerospace, aeronautics, automotive and mobility in general, consumer goods, furniture, sporting products and much more.
Once the components to manufacture are wound, the winding mould is proceeded in a curing process that is not needing an autoclave process. Curing is typically conducted at atmospheric pressure at temperatures around 200°C.
Nevertheless, depending on the specification of the application, all combinations of fibre/matrix must be qualified accordingly. This is an absolute must as the mechanical resistance and E-modulus are varying and depend on their manufacturing process. It is key to know these characteristics to have a reference for comparing the results of the FE analysis.
New winding process applications
As the process for design finding, topology optimisation is simulation driven and with this equipment, the gap for industrialised manufacturing process for highly demanding applications is now closed. The result is a new game-changing process, which the German originator and innovator Automotive Management Consulting (AMC) named “xFK in 3D”.
Dimensions can be from 50 x 50 x 50mm up to the size of a car and above. The process itself is not limited. It’s the handling, transport and curing of large components that are potentially limiting.
The manufacturing process is in the qualification process for space applications with ESA and the three largest satellite Integrators of Europe.
The continuous fibre technology xFKin3D is suitable for non-rotationally symmetrical components such as brackets and other complex support elements. xFKin3D overhauls the endless winding process to a higher “D” level, i.e. with the xFKin3D technological process, it enables parts of 3D, 4D & even 5D to be produced, bringing intelligent functions to the structure if required.
Weight can be reduced by 70% compared to bionic optimised aluminium parts. It is a fully digital process following the bionic design principles of “form follows force”.
xFKin3D is characterised by a number of technical features. First is its high geometric flexibility (e.g. bionic design), followed by its optimised bionic topography (the fibre design is based on load direction). Other notable features include force and tension being optimised (fibre strength/direction according to load), and definable/adjustable strength and stiffness. It features multi-axial load capacity (tension/compression, bending, torsion) and is also material-optimised/resources friendly (almost any offcut). A final noteworthy feature is the integration of functions in the component, bringing the component to an intelligent “5D” component.
In terms of stiffness and especially tensile strength, it is not possible to build “lighter” because “only” as many fibres as necessary are used to fulfil the requirements. Therefore, we speak of an additive manufacturing process of ultra-light construction. “Industry 4.0” is on many people’s lips and is understood as the digitalisation of industry. The targeted networking of industrial structures in an effective networking of efficient software applications is of importance here - i.e. the process from the idea and concept through simulative development and testing to the final production of the component. This is where xFKin3D process technology comes in for ultra-lightweight construction, as the product creation process can be accelerated with this innovative method. Here, calculation and simulation determine the entire subsequent product creation process– the process technology is de facto calculation/simulation-driven, based on the principle “form follows force”. Therefore, we also speak of a “full digital process chain”.
Claude Maack is managing director of Gradel