Reconstruction and Quantitative Characterization of Multiphase, Multiscale Three-Dimensional Microstructure of a Cast Al-Si Base Alloy

Abstract

The serial sectioning technique is well known for the reconstruction of three-dimensional (3D) microstructures of opaque materials. In recent years, techniques also have been developed for the reconstruction of high-fidelity, large-volume segments of 3D microstructures that use montage serial sections and robot-assisted automated acquisitions of montage serial sections. This article reports the reconstruction of the multiphase, multiscale 3D microstructure of a permanent mold cast unmodified Al-12 wt pct Si-1 wt pct Ni base alloy that contains eutectic Si platelets, coarse primary polyhedral Si particles, Fe-rich script intermetallic particles, and pores. These constituents are segmented, reconstructed, rendered, and characterized in three dimensions. The estimated 3D microstrucutral attributes include the distribution of eutectic platelet thickness; the mean volume, mean surface area, and mean thickness of the eutectic Si platelets; the mean volume and the mean surface area of the polyhedral primary Si particles; and the mean number of faces, edges, and corners on the polyhedral primary Si particles.

Three-dimensional visualization and characterization of morphology and internal microstructural features of primary silicon crystals in a cast Al–Si base alloy

“…In this manner, an aligned stack of 80 montage serial sections enclosing 1.02 Â 10 9 mm 3 of 3D microstructural volume was obtained. The details of the procedures for montage serial sectioning and the alignment of the montage serial sections are described elsewhere [9]. Note that although the present microstructure contains numerous constituents (see Figs.…”

“…The primary Si crystals form at relatively low levels of undercooling of the Al-Si alloy melts; they are usually faceted; and they have a wide variety of morphologies [4][5][6][7][8][9]. The majority of primary Si crystals have an octahedral shape formed by the octahedral faces along densely packed {111} planes of the diamond cubic crystal lattice of Si [4].…”

“…For the microstructural features in the cast Al-Si alloys, montage serial sectioning is the suitable and convenient technique for 3D microstructure reconstruction. Recently, a high-resolution large-volume segment of multi-phase 3D microstructure of a permanent mold cast unmodified Al-12 wt% Si-1 wt% Ni base alloy has been reconstructed [9] using the montage serial sectioning technique [15,16]. The reconstructed 3D microstructure volume contains numerous microstructural constituents including primary Si crystals.…”

Multiscale tomographic analysis of heterogeneous cast Al‐Si‐X alloys

“…Light optical tomography (LOT) is a combination of serial sectioning and recording of light optical microscopic images used for 3D reconstructions (Singh et al, 2009). Samples of theAlSi12Ni and AlSi10Cu5Ni2 alloys were polished on a Tegra Pole 31 Struers machine.…”

A Visual Approach to Efficient Analysis and Quantification of Ductile Iron and Reinforced Sprayed Concrete

“…Currently, there is no information published when this part will become available. To evaluate the 3D shape of the graphite particles, metallographic serial sectioning techniques [17] can be used. For the special case of flake graphite, a 3D approach using focused ion beam (FIB) is used to investigate the whole network of spatially interconnected particles [20].…”