Shot-Peening of Pre-Oxidized Plates of Zirconium: Influence of Residual Stress on Oxidation

Laura Raceanu (1) , Virgil Optasanu (1) , Tony Montesin (1) , Guillaume Montay (2) , Manuel François (2)

1 ICB - Laboratoire Interdisciplinaire Carnot de Bourgogne
2 LASMIS - Laboratoire des Systèmes Mécaniques et d'Ingénierie Simultanée

The present study deals with oxidation behavior under residual stress of shot-peened plates of ''commercially pure'' zirconium exposed for 30 min at 650 C. The influence of the shot-peening on a pre-oxidized material is presented. The results have been used to determine the influences of these chemical (preoxidation) and mechanical (shot-peening) treatments on the high temperature oxidation of zirconium. The oxygen profile was revealed using micro-hardness techniques and confirmed by SEM-EDS techniques. After pre-oxidation the samples were first resurfaced then shot-peened in order to introduce residual stress. A significant increase of the hardness of about 400 HV was observed on pre-oxidized shot-peened samples. Thermogravimetric analysis for 30 min at 650 C under 200 mbar O2 showed a significantly slower oxidation rate for shot-peened samples. A comparison with our computations points out the role of the residual stresses on the diffusion and, consequently, on the oxidation.

Mots clés: Oxidation; Stress-diffusion coupling; Shot-peening; Zirconium

Domaines: Matériaux; Matériaux et structures en mécanique [physics.class-ph]; Matériaux et structures en mécanique [physics.class-ph]; Matériaux

Laura Raceanu, Virgil Optasanu, Tony Montesin, Guillaume Montay, Manuel François. Shot-Peening of Pre-Oxidized Plates of Zirconium: Influence of Residual Stress on Oxidation. Oxidation of Metals, 2013, available online - to be published in paper form. ⟨10.1007/s11085-012-9336-0⟩. ⟨hal-00771509v1⟩