Philips Sean P, Tetteh Abigail, Di Prima Matthew A, Burchi Albert, Porter Daniel A
Division of Applied Mechanics, Office of Science and Engineering Laboratories, Center for Devices and Radiological Health, United States Food and Drug Administration, 10903 New Hampshire Ave., WO62-2215, MD, 20993, USA.
EOS North America, Novi, MI, 48377, USA.
3D Print Med. 2024 Apr 8;10(1):11. doi: 10.1186/s41205-024-00212-3.
Multi-laser Additive Manufacturing systems hold great potential to increase productivity. However, adding multiple energy sources to a powder bed fusion system requires careful selection of a laser scan and inert gas flow strategy to optimize component performance. In this work, we explore four different laser scan and argon flow strategies on the quasi-static compressive mechanical response of Body Centered Cubic lattices. Three strategies employ a swim lane method where laser pathing tends to progress parallel to argon flow. Method one only uses a single laser while method two uses four, both with the laser path working against the argon flow. The third method uses four lasers, each operating in their own lane like the second method, but the laser pathing progresses with the argon flow. The fourth method has all four lasers operating in quadrants and the laser pathing trends against the argon flow.The single-laser strategy generally had the lowest mechanical responses compared to the other three strategies. A quadrant strategy generally had the highest quasi-static mechanical responses and was at least 25% greater in stiffness, yield force, ultimate force, and energy absorption when compared to the single laser strategy. However, the four-laser swim strategy where the laser pathing tends against the argon flow was found to be statistically similar to the quadrant strategy. It is hypothesized that spatter introduced onto the powder layer from the melt pool and particle entrainment may be worse for laser pathing which trends with the argon flow direction. Additionally, the additional energy added to the build volume helps to mitigate inter-layer cool time which reduces temperature gradients. This shows that multi-laser AM systems have an impact on part performance and potentially shows lattices built with multi-laser AM systems may have certain advantages over single-laser AM systems.
多激光增材制造系统在提高生产率方面具有巨大潜力。然而，在粉末床熔融系统中添加多个能量源需要仔细选择激光扫描和惰性气体流动策略，以优化部件性能。在这项工作中，我们探索了四种不同的激光扫描和氩气流动策略对体心立方晶格准静态压缩力学响应的影响。三种策略采用泳道方法，其中激光路径倾向于与氩气流动方向平行。方法一仅使用单个激光，而方法二使用四个激光，两者的激光路径均与氩气流动方向相反。第三种方法使用四个激光，每个激光在各自的泳道中运行，与第二种方法相同，但激光路径与氩气流动方向相同。第四种方法是所有四个激光在象限中运行，激光路径趋势与氩气流动方向相反。与其他三种策略相比，单激光策略的力学响应通常最低。象限策略通常具有最高的准静态力学响应，与单激光策略相比，其刚度、屈服力、极限力和能量吸收至少高25%。然而，发现激光路径与氩气流动方向相反的四激光泳道策略在统计上与象限策略相似。据推测，从熔池溅到粉末层上的飞溅物和颗粒夹带对于与氩气流动方向相同的激光路径可能更不利。此外，添加到构建体积中的额外能量有助于减轻层间冷却时间，从而降低温度梯度。这表明多激光增材制造系统对零件性能有影响，并且可能表明用多激光增材制造系统构建的晶格可能比单激光增材制造系统具有某些优势。
