Skip to Main content Skip to Navigation
Theses

Etude de matériaux polymères comme confinement solide dans l’application choc laser LSP

Abstract : The laser shock peening process is commonly used in the aerospace industry. It consists in focusing a laser pulse at the surface of a metallic piece to reinforce its fatigue behaviour properties. When the laser pulse hits the surface of the material, a plasma is created and starts to expand in the air. This plasma release induces the creation of a shockwave with a typical pressure in the GPa range that plasticises the matter. As a result, compressive residual stresses are induced in the material. They are themselves the cause of the final improved fatigue behaviour. In order to produce sufficient pressures to treat the alloys of interest, a water layer is usually placed on top of the surface of the metallic target in the form of running water brought by a little hose. This configuration hinder the plasma expansion in the air and induces the production of higher maximum pressures during a longer duration. However, this configuration does not allow for the treatment of some specific parts of aircrafts that cannot support water in their environment. For this reason, an alternative to the water confined regime is necessary. In this work, the use of flexible, transparent polymers is studied and demonstrates good results allowing to consider polymer as a true candidate for all the laser peening applications where water cannot be used. After a state of the art and a presentation of the materials and methods used during the work, a first part describes the choice, parametric study and residual stresses measurements realised with polymer confinement on an aeronautic alloy while a second part presents the flexible polymer mechanical behaviour under laser conditions (high pressure and strain rate).
Complete list of metadata

https://pastel.archives-ouvertes.fr/tel-03719342
Contributor : ABES STAR :  Contact
Submitted on : Monday, July 11, 2022 - 10:32:43 AM
Last modification on : Friday, August 5, 2022 - 3:33:42 PM

File

107456_LE-BRAS_2022_archivage....
Version validated by the jury (STAR)

Identifiers

  • HAL Id : tel-03719342, version 1

Citation

Corentin Le Bras. Etude de matériaux polymères comme confinement solide dans l’application choc laser LSP. Mécanique des matériaux [physics.class-ph]. HESAM Université, 2022. Français. ⟨NNT : 2022HESAE006⟩. ⟨tel-03719342⟩

Share

Metrics

Record views

41

Files downloads

28