Using Bessel Beams To Enhance Metal 3D Printing Technology

In order to solve the problems of pores and defects in metal 3D printing, researchers at Lawrence Livermore National Laboratory (LLNL) in the United States experimented with exotic optics called Bessel beams. Beam shape. They found that this beam is self-correcting and non-diffractive, and reduces the occurrence of pore formation and "keyholing", while the use of Gaussian beams exacerbates the phenomenon of pore induction. Related findings were published in the journal "Science Advances".

Laser-based 3D printing technology greatly expands the complexity of the design, but the traditional laser beam used for metal printing may cause product defects and poor mechanical performance. To solve this problem, LLNL researchers have explored replacing the commonly used Gaussian beam with other beams in high-power laser printing. The researchers said that the use of Bessel beams can place energy far from the center, which can actively design thermal curves and reduce thermal gradients to optimize the formation of microstructures, thereby obtaining finer devices and smoother surfaces. The Bessel beam greatly expands the parameter space of laser scanning and realizes the ideal molten pool shape: neither too shallow nor bonding. Bessel beams can provide greater depth of focus due to their non-diffraction characteristics.