Liquid silicon infiltration: description of infiltration dynamics and silicon carbide formation

• Published in: Composites. Part A, Applied science and manufacturing Applied science and manufacturing, 1997, Vol.28 (4), p.355-364
• Main Authors: Gern, Frank H., Kochendörfer, Richard
• Format: Article
• Language: English
• Subjects: Analysis and structure; Applied sciences; Building materials. Ceramics. Glasses; Ceramic industries; Chemical industry and chemicals; Exact sciences and technology; General studies; infiltration behaviour; liquid silicon infiltration; Polymer industry, paints, wood; Properties and testing; simulation; Technical ceramics; Technology of polymers
• ISSN: 1359-835X; 1878-5840
• DOI: 10.1016/S1359-835X(96)00135-2

This article presents a model for the numerical simulation of liquid silicon infiltration into porous carbon/carbon preforms. Based upon the special morphology of the preforms, capillary flow has been modelled using a one-dimensional solution of the Navier-Stokes equations. To calculate macroscopic infiltration behaviour of porous components like plates or tubes, microscopic capillary flow phenomena have been linked with macroscopic silicon concentration via the statistical distribution function of capillary diameters. As a result, the time dependence of silicon concentration during infiltration as well as silicon distribution in the ceramic end-product can be calculated. The same model is also suitable for calculating the degree of silicon conversion to silicon carbide and therefore the phase composition of the fabricated ceramic material. Simulation values of silicon concentration and phase composition show good accordance with experimental measurements.