  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.
