RFC has successfully manufactured a prototype energy shaft. It was cast, forged and underwent the required heat treatment operations.
After careful planning, manufacturing was carried out with no significant deviations neither in chemical composition nor in subsequent process setpoints. RFC personnel has been closely monitoring the response of the material on every critical process, recording valuable data that will later be used by the Project Partners to calibrate their models, design their experiments and develop the Life Cycle Assessment.
RFC´s R&D Team have also developed a computational FE model to assist Engineering into re-designing the heat treatment maintenance times, affecting the stages of controlled cooling and normalizing. This was a very important task to be performed ahead of manufacturing, as the ingot presents different dimensions to the typical ones that are produced for these products.
The general trends predicted by the simulation were validated in the industrial environment using a contact thermocouple, confirming the validity of the model and thus ensuring the formation of the required microstructure.
Just data was not the only thing that was collected throughout the process. Additionally, material has been retrieved from the top and bottom ends of the ingot on its final stage of forging via oxygen-cutting. This was done with care of keeping the original microstructure intact, so the characteristics of the steel at that stage could be explored. This will provide valuable information to Fraunhofer IWM for adjusting their forging model.
After verifying the absence of cracks within the shaft via ultrasonic inspection, the shaft was marked to ensure traceability of its position within the furnace during heat treatment. Then, it was finally sent to the Machining Workshop with instructions for producing a number of samples for the different Partners, namely UOulu, ULiege and again Fraunhofer. These samples will allow to test the compression behaviour during forging and to produce detailed experimental plots for physical properties and phase transformations during cooling.
The shaft has been sectioned and the first batch of samples was distributed to the project’s various technological partners, who will use them to characterise the material in detail and thus calibrate their forging and hardening simulation models.
Meanwhile, to establish a firm basis for the microstructure-related work in the project, OCAS NV produced several samples of Advanced High Strength Steels (AHSS). By varying the chemical composition and processing route, 14 different microstructures were generated. The samples were delivered to Ghent University for further microscopic investigations. This breakthrough concludes the first stage of the process, grouping the casting, forging and preliminary heat treatment operations.
Thanks to AID4GREENEST, funded by the European Union’s Horizon Europe programme, RFC will be able to identify potential steel production failures in advance and in this way, reducing both the production of components that end up being discarded and the environmental impact of steel manufacturing.
