In the present study, a combination of high-throughput (HT) and low-throughput (LT) techniques was used to rapidly determine the processing window and generate processing maps for Selective Laser Melting (SLM) of 316L stainless steel. The HT method includes the fabrication of hundreds of hex nut-shaped specimens, each processed with a unique combination of laser power, scanning speed, and hatch spacing. An easily removable scaffolding permitted rapid sample extraction from the base plate, thus saving machining cost and time. Hardness and immersion density measurements were used for HT characterization to identify a processing window for maximum strength and density. Within the defined processing window, a low-throughput (LT) microstructural interrogation of specimens were performed. The microstructural analysis included quantification at various length scales (i.e., grains size and morphology, texture, primary dendrite arm spacing, and melt pool geometry analysis). Microstructure-based processing maps as a function of volumetric energy density were generated. The combination of HT and LT methods produced a predictive relationship between hardness and primary dendrite arm spacing using a Hall-Petch relationship. A model is proposed to explain the dependence of microstructure on the melt pool geometry. The HT method can be applied for the microstructural design of SLM-fabricated components in other alloys.

在本研究中，高通量（HT）和低通量（LT）技术的组合用于快速确定316L不锈钢的选择性激光熔炼（SLM）的加工窗口并生成加工图。HT方法包括制造数百个六角形螺母状样本，每个样本都经过激光功率，扫描速度和舱口间距的独特组合处理。易于拆卸的脚手架可从基板上快速提取样品，从而节省了加工成本和时间。硬度和浸没密度测量用于HT表征，以确定最大强度和密度的加工窗口。在定义的处理窗口内，对标本进行了低通量（LT）显微组织询问。微观结构分析包括在各种长度尺度上的量化（即晶粒尺寸和形态，织构，主要枝晶臂间距和熔池几何分析）。生成了基于微结构的加工图，该图是体积能量密度的函数。HT和LT方法的结合使用Hall-Petch关系在硬度和主要枝晶臂间距之间产生了预测关系。提出了一个模型来解释微结构对熔池几何形状的依赖性。HT方法可用于其他合金中SLM制造的部件的微观结构设计。HT和LT方法的结合使用Hall-Petch关系在硬度和主要枝晶臂间距之间产生了预测关系。提出了一个模型来解释微结构对熔池几何形状的依赖性。HT方法可用于其他合金中SLM制造的部件的微观结构设计。HT和LT方法的结合使用Hall-Petch关系在硬度和主要枝晶臂间距之间产生了预测关系。提出了一个模型来解释微结构对熔池几何形状的依赖性。HT方法可用于其他合金中SLM制造的部件的微观结构设计。