Ansari Md Jonaet, Nguyen Dinh-Son, Park Hong Seok
Department of Mechanical Engineering, University of Ulsan, Ulsan 44601, Korea.
Materials (Basel). 2019 Apr 18;12(8):1272. doi: 10.3390/ma12081272.
Selective laser melting (SLM) is an additive manufacturing (AM) technique that has the potential to produce almost any three-dimensional (3D) metallic part, even those with complicated shapes. Throughout the SLM process, the heat transfer characteristics of the metal powder plays a significant role in maintaining the product quality during 3D printing. Thus, it is crucial for 3D-printing manufacturers to determine the thermal behavior over the SLM process. However, it is a significant challenge to accurately determine the large temperature gradient and the melt pool size using only experiments. Therefore, the use of both experimental investigations and numerical analysis can assist in characterizing the temperature evaluation and the melt pool size in a more effective manner. In this study, 3D finite element analysis applying a moving volumetric Gaussian laser heat source was used to analyze the temperature profile on the powder bed and the resultant melt pool size throughout the SLM process. In the experiments, a TELOPS FAST-IR (M350) thermal imager was applied to determine the temperature profile of the melting pool and powder bed along the scanning direction during the SLM fabrication using TiAlV powder. The numerically calculated results were compared with the experimentally determined temperature distribution. The comparison showed that the calculated peak temperature for single- and multi-track by the developed thermal model was in good agreement with the experiment results. Secondly, the developed model was verified by comparing the melting pool size for various laser powers and scanning speeds with the experimentally measured melting pool size from the published literature. The developed model could predict the melt pool width (with 2-5% error) and melt pool depth (with 5-6% error).
选择性激光熔化（SLM）是一种增材制造（AM）技术，有潜力制造几乎任何三维（3D）金属部件，即使是那些形状复杂的部件。在整个SLM过程中，金属粉末的传热特性在3D打印过程中保持产品质量方面起着重要作用。因此，对于3D打印制造商来说，确定SLM过程中的热行为至关重要。然而，仅通过实验准确确定大的温度梯度和熔池尺寸是一项重大挑战。因此，结合实验研究和数值分析可以更有效地帮助表征温度评估和熔池尺寸。在本研究中，应用移动体积高斯激光热源的三维有限元分析被用于分析粉末床的温度分布以及整个SLM过程中产生的熔池尺寸。在实验中，使用了一台TELOPS FAST-IR（M350）热成像仪来确定在使用TiAlV粉末进行SLM制造过程中沿扫描方向的熔池和粉末床的温度分布。将数值计算结果与实验确定的温度分布进行了比较。比较结果表明，所开发的热模型计算的单道和多道峰值温度与实验结果吻合良好。其次，通过将不同激光功率和扫描速度下的熔池尺寸与已发表文献中实验测量的熔池尺寸进行比较，验证了所开发的模型。所开发的模型能够预测熔池宽度（误差为2 - 5%）和熔池深度（误差为5 - 6%）。
