Hybrid experimental-numerical concept of residual stress analysis in laser weldments

The concept, methodology and instrumentation for hybrid experimental-numerical residual stress analysis in a laser weldment are presented. Grating interferometry and digital speckle photography are applied as complementary experimental methods for the determination of the initial model of residual strains and of the material properties at the various zones of a laser weldment. These data inserted into a finite element model enable one to analyze the formation of the residual stress state of the object, which is compared and modified by means of experimental data in a closed iterative loop. This full hybrid approach is tested successfully on a laser-welded steel specimen in uniaxial tensile tests.