Ultrafast laser-enabled 3D metal printing: A solution to fabricate arbitrary submicron metal structures

3D metal printing has become one of the critical manufacturing methods in recent years that enables a variety of applications across different disciplines, e.g. aerospace and medicine. In this work, we present a high-throughput 3D metal printing method based on a programmable femtosecond light sheet and electrodeposition, achieving submicron resolution in both lateral and axial directions. The light sheet, for parallel material removal, is generated by spatially and temporally focusing the ultrafast laser in the processing plane, which is in conjugation with a digital micromirror device (DMD), thereby allowing fast pattern generation in synchronization with laser pulses. High quality metal layers are formed successively via electrodeposition processes. Accordingly, 3D metal printing is realized by repeating the steps of (1) forming structural/sacrificial layers; and (2) laser micro machining. In the experiments, we demonstrate fast metal printing of various complex 3D structures within tens of laser pulses over an area of 100 x 60 mu m(2). Compared with the existing sequential metal printing techniques, the new method has substantially improved both the throughput and resolution by a factor of similar to 100 times.