Additive Manufacturing of a Laser Heat Sink: Multiphysical Simulation for Thermal Material Requirement Derivation

Heat dissipation inside diode-pumped Nd:YVO4 laser crystals requires an efficient cooling concept to reduce heat-induced stress and thus to avoid the mechanical destruction of the laser medium. Due to a high degree of design freedom, additive manufacturing of heat sinks offers great potentials to integrate cooling channels and sensors within a single component. These advantages are associated with a reduced choice of materials. The thermal and mechanical properties of the printing material have a significant impact on the emerging stress. For a suitable choice of printing material, temperatures and stress occurring in the application of the product are calculated using a multi-physical simulation model. By coupling optical, thermal and mechanical effects within a single simulation model, the mechanical stress in the laser crystal is investigated as a function of thermal material properties. Based on this information, thermal requirements are defined to ensure a non-destructive operation of a present laser application.