Controlling the texture evolution to help tailor the mechanical properties is crucial in the laser powder bed-fusion (L-PBF) of superalloy. Previous studies demonstrated a crystallographic lamellar microstructure (CLM) which had a high strength and high ductility due to the presence of a unique interface between <110>-oriented main and <100>-oriented sub-layer. However, the thorough understanding of their formation mechanism and the control method of the periodic CLM remains nebulous. In this study, the growth behavior of the CLM has been clarified by schematic analysis combined with the transmission electron microscopy (TEM) analysis. Four types of unique periodicity CLM are successfully designed through computational fluid dynamics (CFD) approaches, which provides more potential future directions for developing structural applications in L-PBF directional solidification superalloy.

控制织构演变以帮助调整机械性能对于高温合金的激光粉末床熔合 (L-PBF) 至关重要。先前的研究表明，由于<110>取向的主层和<100>取向的子层之间存在独特的界面，晶体层状微观结构（CLM）具有高强度和高延展性。然而，对其形成机制和周期性CLM控制方法的透彻理解仍然模糊。在本研究中，通过示意图分析结合透射电子显微镜（TEM）分析阐明了 CLM 的生长行为。通过计算流体动力学（CFD）方法成功设计了四种独特周期性CLM，为L-PBF定向凝固高温合金结构应用的开发提供了更多潜在的未来方向。