Multidroplet Impact Model for Prediction of Residual Stresses in Water Jet Peening of Materials

Abstract

In this article, a multidroplet impact model, proposed for predicting residual stresses induced on materials subjected to water jet peening, is presented. This approach considers the impact pressure distribution due to high-velocity droplets impinging on the material surface instead of stationary pressure distribution for prediction of residual stresses on water jet-peened surfaces. It makes use of Reichardt's theory for predicting the velocity distribution of droplets and liquid impact theory for predicting the impact pressure and duration of impact of high-velocity droplets. For predicting residual stresses on the surface and subsurface of material subjected to water jet peening, finite element modeling approach was adopted by using transient elastoplastic finite element analysis by considering an impingement of a set of droplets in succession to one another over a certain time period after which this pressure is released. The effectiveness of the proposed approach was demonstrated bv comparing the predicted residual stresses with those predicted by using the single set of droplets approach proposed by Rajesh et al. [6]. Finally, the practical relevance of the proposed approach was shown by comparing the predicted results with the experimental results obtained by water peening of 6063-T6 aluminium alloy.

Keywords:

• Numerical modeling
• Residual stresses
• Surface treatment
• Transient dynamic analysis
• Water jet peening

Notes

1 – predicted with single set of droplets, 2 – predicted after second set of droplets. 3 – predicted after third set of droplets, and 4 – predicted after fourth set of droplets.