Precision micro-particle removal from through-holes via laser-induced plasma shockwaves in additive manufacturing

This study introduces a novel Laser-Induced Plasma (LIP) technique for the non-contact, rapid removal of nano and microparticles from through-holes in Additive Manufacturing (AM) components. This method is crucial for high-value applications, such as medical devices, compact heat exchangers, and aerospace engineering, which require efficient cleaning of intricate parts with holes and channels to address high failure costs. The technique leverages shockwaves generated by LIP to target and clean these complex geometries. The research focuses on two main areas: (i) characterizing the effects of shockwaves in semi-cylindrical channels to understand interactions with complex geometries, and (ii) quantitatively analyzing the removal of Fe-271 microparticles from semi-cylindrical channels of silicon (Si) wafers, selected for their consistent surface properties compared to the rough textures of AM-produced surfaces. Utilizing the experimental set-up Laser-Induced Plasma LIP Cleaning for Additive Manufacturing (LIPCAM), the study demonstrates that complete microparticle removal is achievable up to 20 mm from the plasma source with variable laser pulses. The results indicate that particles larger than 27 μm are entirely removed after a single pulse, and particles larger than 21 μm are removed after 50 pulses. These findings highlight the method's effectiveness in achieving high particle removal efficiency across different distances and particle sizes, thus ensuring thorough decontamination of complex internal structures. The study underscores the potential of this method to enhance the reliability and safety of critical AM builds, making it a viable solution for industries where precision and cleanliness are paramount.