AFX360° | Amaero | Increased productivity for crack-prone materials enabled by nLIGHT AFX-1000

Live presentation of Kenneth Davis (Amaero) at Formnext 2022 in Frankfurt on November 15th 2022
As a result of the continuous advancements in laser powder bed fusion (L-PBF), we find ourselves at an interesting crossroads. While we were once challenged to print fully dense material with underpowered lasers and inadequate productivity, we now find ourselves unable to fully utilize the available 1 kW of power in the lasers routinely being fielded in L-PBF systems today. We traditionally print with a nominally 80 µm laser spot size for both contouring and hatching as a compromise of productivity, feature resolution and surface finish. Attempting to print with much more than 500 W of power typically results in excessive keyhole porosity and condensate generation. To combat this limitation and to increase productivity, some L-PBF systems employ multiple lasers, numbering from two to twelve. Other systems utilize more of the available laser power by defocusing the beam to a much larger spot size for hatching, while refocusing back to the 80 µm Gaussian spot for contouring. Both approaches drastically increase the complexity of the L-PBF system and create more opportunities for defects. The AFX-1000 multi-mode laser allows nearly instantaneous switching between a Gaussian spot and several sizes of ring modes, without any complicated optics or electro-mechanical systems. Having the ability to switch between these modes allow us to print with the highest possible energy and productivity for each material and application. Presented will be the current results of an ongoing investigation into increased productivity of L-PBF printed Ni718 and H-13 tool steel with the AFX-1000 laser. Recent experiments have demonstrated the ability to print both alloys at layer thicknesses up to 150 µm and with deposition rates exceeding 100 cc/hr.