Fourier‐series‐based virtual fields method combining with moiré interferometry for characterising elastic modulus distribution of laser repaired GH4169

Abstract

Laser cladding is an effective technology for repairing damaged components with high efficiency and low cost. Characterisation for the mechanical properties of the repaired structure is of great importance to evaluate its reliability. In this study, the mechanical properties of laser repaired GH4169 are investigated by Fourier‐series‐based virtual fields method and moiré interferometry. The elastic modulus distribution of the whole structure is identified to understand the mechanical performance of the repaired zone and base material. A uniaxial tensile test is performed and the full‐field deformation is measured by moiré interferometry. With the measured strain field, the distribution of modulus in repaired structures can be calculated. In addition, simulation experiments of moiré interferometry are conducted to optimise the parameters of Fourier‐series‐based virtual fields method to improve the accuracy of the proposed method. On the basis of these results, experiments on the repaired GH4169 material are performed and the variation of modulus in the whole structure is identified. The results verify that the proposed method is effective for characterising modulus distribution of the laser repaired structures, and will have a good prospect for further application.

Identification of thermomechanical parameters based on the virtual fields method combined with the sampling moiré method

“…Full-field deformation measurement is a vital basis of the VFM for characterising the mechanical properties of materials. Optical full-field measurement techniques such as digital image correlation (DIC), [16][17][18] moiré interference (MI), [19][20][21] and the grid method [22,23] can provide a wealth of deformation information for the VFM. In recent years, the sampling moiré (SM) method has rapidly developed as a new moiré technique and has been widely applied in deformation measurements at the macro-and micro-scales.…”