Powder Bed Fusion of highly filigree copper features using a green laser

Abstract

Green lasers offer a way to significantly increase process quality and part performance of copper components manufactured by laser powder bed fusion. However, the larger beam diameters of available green lasers compared to the widely used infrared lasers must not limit minimum feature sizes for demanding applications, such as heat exchangers. Therefore, this study investigates the level of filigree achievable using a green disk laser with a nominal spot diameter of 200 μm. Empirical relations between scanning parameters and achievable feature sizes were established based on the width and depth of single line scans. The results were generalized and transferred to thin walls with build angles of 90° (vertical), 60°, and 30°. Fully dense vertical features with a thickness of about 200 μm at their core were manufactured. Still unresolved formation of solidified drips on the as-built copper part surface were observed, which could be removed by adequate post-processing.