Modeling and simulation of the energy deposition in laser beam welding with oscillatory beam deflection

In recent years, some promising results about laser beam welding with forced beam oscillation were published. Characteristic feature of this technology is the purposeful beam manipulation by an oscillatory beam deflection in superposition to the commonly uniform and rectilinear feed rate of a conventional laser beam welding process. Due to the increased number of welding variables, the application of oscillation techniques offers manifold possibilities to influence the energy deposition in dependence on the chosen oscillation regime. In such a way, the process behavior as well as the resultant properties of the weld can be favorably changed. An appropriate understanding of the interaction among the relevant welding and oscillation parameters was achieved through the modeling of the underlying physical relationships and the simulation of the transient energy deposition during beam oscillation procedures. Different deflection methods and various one- and two- dimensional oscillation patterns have been allowed for. By derivation of suitable dimensionless quantities, the developed model facilitates the distinction and characterization of different process regimes as well as the determination of appropriate oscillation parameters as function of the chosen welding variables.