Modeling the selective laser melting-based additive manufacturing of thermoelectric powders
Modeling the selective laser melting-based additive manufacturing of thermoelectric powders
复制标题
DOI：
10.1016/j.addma.2020.101666
复制
发表时间：
2020-10
影响因子：
11
通讯作者：
Yongjia Wu;K. Sun;Shifeng Yu;L. Zuo
中科院分区：
文献类型：
--
作者：
Yongjia Wu;K. Sun;Shifeng Yu;L. Zuo
热电发电机在暴露于适当的温差时直接将热能转换为电能。由于传统设计和制造方法的缺陷，热电模块的效率尚未得到充分的探索。选择性激光熔化（SLM）增材制造为制造具有高能量转换效率的柔性和功能梯度热电材料提供了一种独特的潜在可扩展方法。本文建立了一个物理模型来模拟SLM制备热电材料（Mg2Si粉末）的过程，其中添加材料（Si）的混合是为了获得更好的热电性能。对SLM制造进行了全面的热和流体研究，以了解与熔池中的熔化和凝固过程相关的现象。该物理模型是基于守恒方程建立的，为研究熔池中浮力和表面张力驱动下的流体流动提供了基础。利用该模型，研究了激光扫描速度和功率密度等工艺参数对粉末床温度分布、粉末床收缩率、熔池尺寸和颗粒聚集的影响，为理解SLM制备热电器件提供了重要信息。
Thermoelectric generators directly convert thermal energy to electricity when exposed to the proper temperature difference. The efficiency of the thermoelectric module has not been fully explored due to the drawbacks in conventional design and fabrication methods. Selective laser melting (SLM) additive manufacturing offers a unique potential scalable approach for the fabrication of flexible and functionally graded thermoelectric materials with high energy conversion efficiency. In this paper, we developed a physical model to simulate the SLM manufacturing process of thermoelectric materials (Mg2Si powders) with additive material (Si) mixed for better thermoelectric performance. A comprehensive thermal and fluid study of the SLM manufacturing was conducted to understand the phenomena associated with the melting and solidification processes in the melting pool. This physical model was established based on the conservation equations and provided a basis to study the fluid flow driven by the buoyancy force and surface tension in the melting pool. Using this model, the influences of the process parameters, such as laser scanning speed and power energy density, on the temperature distribution, powder bed shrinkage, pool size, and particle aggregation in the powder bed, were studied, which provided critical information for understanding SLM for thermoelectric device fabrication.