Measurement of Anode Anisotropy by Micro X-Ray Computed Tomography

Abstract

Micro X-ray Computed Tomography (CT) is an instrumental method for recording inner structure 3D images without damaging the observed volume. A methodology has been developed by SINTEF for CT of carbonaceous materials, yielding detailed structural views and quantification of the pore, void and grain distribution within volumes of 10 mm to 130 mm diameter. Example results are shown from a study of anode anisotropy. A series of vertical cores from a prebaked anode was analysed, selected due to clear difference in top, middle and bottom level structure. The CT data was calibrated and connected to the physical position in the anode. The data was analysed with various methods that quantify the degree of anisotropy. The analysis show that the anodes have a 10-15 cm wide zone of high anisotropy, while the top and bottom of the anode are more isotropic. Some possible reasons for mid-height anisotropy are discussed.

Investigation of Molten Metal Infiltration into Micropore Carbon Refractory Materials Using X-ray Computed Tomography

“…Based on the XCT measurements, methods for determining parameters describing pore structure-tortuosity [23] and constrictivity [24]-were developed. Only for carbon and graphite refractory materials, XCT has been used to investigate the pore structure of micropore carbon materials [25], microstructure and tortuosity analysis of carbon anodes for aluminum smelting [26,27] and for porosity investigations of carbon blocks and ramming paste used for silicomanganese production [28].…”