Full professor at PIMM laboratory (Arts et Metiers Science and Technology), my scientific objective is to improve the understanding of instability phenomena in metal additive manufacturing processes, particularly in LPBF. This includes the study of keyhole instability, spatter generation, the influence of laser beam profiles, and the complex interactions between the liquid melt pool and the powder bed. A central part of my research involves the development of numerical models that strike a balance between physical accuracy and computational efficiency. These models are designed to enable parametric studies, provide reliable process predictions, and ultimately support the implementation of digital twins for advanced manufacturing systems.