In subproject B1, local physical and geometrical effects which have only been observed so far as side effects in the laser joining process, are to be used purposefully, in order to achieve graded strength properties and to improve the component rigidity significantly. One aim of the work in the first requested period is the investigation of effects of laser-based joining connections on the structure rigidity for simplified sample geometries. A defined local strength increase will first be done on blind seams and later on seams with suitable seam geometries. In the context of SFB 675, laser joining processes are to be developed further so that the final assembly can take place with and other methods to increase strength for semi-finished products without considerably changing the local material characteristics. Beyond that, general rigidity effects of the connections are to be used purposefully for rigidity improvement.