residual compressive peening effect

English to French Tech/Engineering Mechanics / Mech Engineering Grenailleuses

"The blue line is the expected stress, (+600 at surface), the grey line is the residual compressive peening effect at surface (-800).
The red line is the resultant when you subtract the expected stress from the residual compressive stress during service."

S'agit-il de "l'effet du grenaillage sur la contrainte résiduelle" ?
D'avance merci !