Processing LDS-Circuit Boards by Selective Laser Sintering

Abstract

Abstract As the demand for individualized products rises, the development and need for additive manufacturing (AM) techniques such as selective laser sintering (SLS) has strongly increased. The industrial use of these procedures for prototypes or small-scale production lines has grown due to their specific characteristics like the high achievable complexity. With the increasing demand for electrification and functionalization, the combination of AM with laser-direct structuring (LDS) gains interest. Therefore, the powder used for the investigation is dry coated with a LDS-additive, which enables laser activation and a metallization of the activated sections in a metallization bath. To characterize the influence of the LDS-additive on the process, the powder properties were investigated for unfilled and successive increased additive content. The thermal process window was identified by standard and process adapted isothermal differential scanning calorimetry. This showed a decrease of the isothermal crystallization time due to nucleation effects of the additive. Subsequently, parts were produced with a parameter study and showed a demand for a higher energy density. The resulting parts were then metallized with a parameter variation and characterized by stereomicroscopy. To investigate the influence of the different parameter sets and the LDS content, the mechanical properties were determined.