In the industrial context of pressurized water reactors (PWR) within the French nuclear power plant fleet, the internal components of PWRs susceptible to wear are subject to special monitoring. Faced with these challenges, EDF and CEA aim to enhance the understanding and prediction of wear phenomena, not only to optimize maintenance operations and improve component design but also to optimize research and development efforts while ensuring the reliability of the obtained results.

Among the technical and scientific objectives set within the framework of their collaboration since 2014, the evolution and improvement of wear testing methods and associated digital tools hold particular importance, including the modeling of the wear phenomenon itself.

The objective of this thesis is to propose a predictive model of wear through an experimental, theoretical, and numerical approach. One of the scientific challenges will be to identify a relevant mechanical parameter that adequately characterizes wear and faithfully represents the driving force behind the phenomenon, from its inception to its propagation, independently of the geometries of the contacting components and the loads they undergo.
From a theoretical point of view, we will operate within the framework of the thermodynamics of continuous media with moving contact surfaces, where wear results from the progressive damage of the material. Recent work initiated at CEA in Quentin CARADEC's thesis [CARADEC] aligns with this approach. The evolution of damage, indicative of wear, is represented there using a thick level-set approach. This approach allows, based on a damage law, the formulation of a law for the propagation of the worn surface. The relevance of this model will need to be verified through a comparison of the results obtained from its numerical implementation with those from experiments that will have been conducted, with a focus on the study of abrasion wear in light of the experience gained from PWRs.

Graduates of top engineering schools or holders of a Master's degree (M2), the candidate should have skills in structural and materials mechanics, and in numerical simulation.

At the end of the thesis, the student's experience can be put to good use in research positions in industry (nuclear, automotive, rail, aeronautics, medical, etc.), and in the academic network.

An M2 internship on the same subject is offered prior to the thesis. Applying for this internship is not a requirement for the thesis, but it could be an asset for the student.

[CARADEC]: Caradec, Q. (2023). On the modeling and numerical simulation of fretting wear. PhD thesis, Institut Polytechnique de Paris.