Stress Relaxation in Shot-Peened Geometric Features Subjected to Fatigue: Experiments and Modelling

Abstract:

This paper investigates experimentally and numerically the degree to which the stress relaxation in shot-peened simple geometric features of steel turbine materials can be modelled by using an understanding of simple eigenstrain distributions. The residual stress is determined as the elastic response of whole component when the plastic strains caused by shot peening is incorporated as an eigenstrain in an appropriate finite element (FE) model. The application of a subsequent live load is then modelled as an additional load step in the FE model which will superpose the effect of this loading on the residual stress field. The results show that the eigenstrain approach is particularly useful in predicting residual stress relaxation in shot-peened components.

• Periodical: Advanced Materials Research (Volume 996)
• Pages: 729-735
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.996.729
• Online since: August 2014
• Authors: Mithila Achintha*, Chao You, Bin Yan He, Kath Soady, Philippa Reed
• Keywords: Eigenstrain, FE Analysis, Residual Stress, Stress Relaxation

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