2025 - 2028
To address this challenge, researchers are developing new repair approaches based on metal additive manufacturing. At Centrale Nantes, Lucas Lestandi, a researcher, works on a process where we could repair a piece by depositing molten metal layer by layer.
Unlike 3D printing, which is used to manufactured an entire part, this technology makes it pos-sible to restore only damaged areas. The aim is to give to the part her mechanical property back while extending its lifespan.
Repairing a metal part is not simply a matter of adding material. During the deposition pro-cess, the metal undergoes very rapid heating and cooling cycles that can lead to the formation of defects. If these phenomena are not properly controlled, the repair may weaken the part rather than reinforce it. Researchers are therefore seeking to better understand the physical mechanisms involved during the process in order to ensure reliable and reproducible repairs. To achieve this, they combine several scientific approaches, including numerical models ca-pable of simulating material behaviour, together with experimental validation. The knowledge gained is then used to develop AI algorithms capable of anticipating defects
One of the major innovations of the SAMSARA project is the development of a digital twin of the repair process. This virtual replica reproduces the behaviour of the real process and makes it possible to test numerous configurations before carrying out more extensive workshop trials. Researchers can therefore predict the influence of different parameters, adjust manufacturing conditions and identify the best repair strategies while limiting the number of physical exper-iments. This approach accelerates the development of new processes while reducing material and energy consumption.
Jointly led by French and Singaporean teams, the SAMSARA project aims to make repair pro-cesses more precise, reliable and resource-efficient. In the long term, this research could en-able industrial companies to repair more components, extend their service life and reduce the consumption of raw materials, thereby contributing to a more circular industry.
Lucas Lestandi is a researcher at Centrale Nantes, within the MECNUM team at the Institute of Civil and Mechanical Engineering (GeM).
He graduated as an engineer from ENSEIRB-MATMECA in Bordeaux in 2015 and obtained his PhD in Mechanical Engineering from the University of Bordeaux in 2018.
His research focuses on model reduction, a branch of numerical modelling dealing with me-chanical phenomena and processes.
Computational mechanics is a mature discipline, and with sufficient computing power, it is possible to model most systems encountered in engineer-ing.
