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arXiv · 1411.4535

Generalized balanced power diagrams for 3D representations of polycrystals

Andreas Alpers·Andreas Brieden·Peter Gritzmann·Allan Lyckegaard·Henning Friis Poulsen
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Abstract

Characterizing the grain structure of polycrystalline material is an important task in material science. The present paper introduces the concept of generalized balanced power diagrams as a concise alternative to voxelated mappings. Here, each grain is represented by (measured approximations of) its center-of-mass position, its volume and, if available, by its second-order moments (in the non-equiaxed case). Such parameters may be obtained from 3D x-ray diffraction. As the exact global optimum of our model results from the solution of a suitable linear program it can be computed quite efficiently. Based on verified real-world measurements we show that from the few parameters per grain (3, respectively 6 in 2D and 4, respectively 10 in 3D) we obtain excellent representations of both equiaxed and non-equiaxed structures. Hence our approach seems to capture the physical principles governing the forming of such polycrystals in the underlying process quite well.

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Andreas Alpers, Andreas Brieden, Peter Gritzmann, Allan Lyckegaard, Henning Friis Poulsen. 2015-01-28. Generalized balanced power diagrams for 3D representations of polycrystals. https://doi.org/10.1080/14786435.2015.1015469

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