A novel approach to reconstruct residual stress fields induced by surface treatments in arbitrary 3D geometries using the eigenstrain method

Abstract

A novel approach has been proposed to reconstruct residual stress fields after surface treatments in arbitrary 3D geometries using the eigenstrain method based on bicubic spline interpolation surface and finite element (FE) method. Firstly, the complex curved surface is represented by piecewise interpolation of the smooth surface using explicit bicubic functions, then the computation of the distance and corresponding orientation are calculated by solving a constrained nonlinear multivariable problem using MATLAB, which is insensitive to the complexity of the curved treated surface and reduces the errors induced by differentiation operations when using Wall distance module in COMSOL in previous works. Three instances of 3D geometries after surface treatment studied previously in literature and finally an instance of a real turbine blade after LSP treatment conducted by ourselves are analyzed, which validate the proposed approach and illustrate its effectiveness in the reconstruction of residual stress fields for complex 3D geometries in various cases. The proposed approach provides a general and flexible way to the implementation of eigenstrain method in arbitrary 3D geometries using data interchange between the mathematical calculation software and FE analysis software for the design in industrial applications.