Zaikovska Liene, Ekh Magnus, Gupta Mohit, Moverare Johan
Department of Engineering Science, University West, SE-461 86 Trollhättan, Sweden.
Department of Material and Computational Mechanics, Chalmers University of Technology, SE-412 06 Gothenburg, Sweden.
Materials (Basel). 2024 Dec 4;17(23):5937. doi: 10.3390/ma17235937.
Additive manufacturing (AM) methods like powder bed fusion-laser beam (PBF-LB) enable complex geometry production. However, understanding and predicting the microstructural properties of AM parts remain challenging due to the inherent non-homogeneity introduced during the manufacturing process. This study demonstrates a novel approach for 3D microstructure representation and virtual testing of non-homogeneous AM materials using 2d electron backscatter diffraction (EBSD) data. By employing the representative volume element (RVE) method, we reconstruct the 3D microstructure from 2D EBSD datasets, effectively capturing the grain morphological characteristics of PBF-LB-produced Hastelloy X. Using validated RVE data, we artificially generate combinations of two grain textures to gain deeper insight into locally affected areas, particularly the stress distribution within the interfaces, as well as global material behavior, exploring non-homogeneity. Computational homogenization (CH) utilizing a crystal elasticity finite element (CEFE) method is used to virtually test and predict directional elastic properties, offering insights into relationships between microstructure evolution and property correlation. The experimentally validated results show a strong correlation, with only 0.5-3.5% correlation error for the selected grain tessellation method. This consistency and reliability of the methodology provide high confidence for additional virtual tests predicting the properties of non-homogeneous, artificially generated combined-grain structures.
诸如粉末床熔融激光束（PBF-LB）之类的增材制造（AM）方法能够生产复杂的几何形状。然而，由于制造过程中引入的固有不均匀性，理解和预测增材制造零件的微观结构特性仍然具有挑战性。本研究展示了一种使用二维电子背散射衍射（EBSD）数据对非均匀增材制造材料进行三维微观结构表征和虚拟测试的新方法。通过采用代表性体积单元（RVE）方法，我们从二维EBSD数据集中重建三维微观结构，有效捕捉了PBF-LB工艺制造的哈氏合金X的晶粒形态特征。利用经过验证的RVE数据，我们人工生成两种晶粒织构的组合，以更深入地了解局部受影响区域，特别是界面内的应力分布以及整体材料行为，探索不均匀性。利用晶体弹性有限元（CEFE）方法的计算均匀化（CH）用于虚拟测试和预测方向弹性性能，深入了解微观结构演变与性能相关性之间的关系。实验验证结果显示出很强的相关性，对于所选的晶粒镶嵌方法，相关误差仅为0.5-3.5%。该方法的这种一致性和可靠性为预测非均匀、人工生成的组合晶粒结构性能的额外虚拟测试提供了高度的信心。
