Contraintes de grenaillage du superalliage in 100

Influence du temps et de la température

nfluence of temperature and time on the stress relaxation process of shot peened in 100 superalloy

¹ ENSAM, Paris
² TURBOMECA, Tarnos, France

Abstract

A theorical model, based on experimental results, has been developed in order to predict the thermal stability of residual stresses induced by shot peening in IN 100 superalloy turbine blades.

Surface residual stress determination has been carried out using a X-Ray diffractometry technique. Residual stress profiles vs depth in the affected layer have been determined using the incremental hole drilling method.

Consequently, it has been possible to propose an optimized shot peening processing which greatly differs from the actual set of parameters used up to now.

High velocity projection of small steel shots results in detrimental effects which are to be avoided. On the other hand, low velocity projection of large shots of high density material generates high-level residual stresses showing outsanding thermal stability at service temperature of the turbine blade.