| Abstract
| - Exothermic reactions between a porous matrix and an infiltrating melt provide a more economicalternative for synthesizing many ceramics, intermetallics, and composites. It has recently beendemonstrated that infiltration of cast microporous carbon preforms by silicon melt can be usedto fabricate high-density, nearly net-shaped silicon carbide components at significantly reducedcost. This paper describes the synthesis of reaction-bonded silicon carbide by reactive infiltrationof microporous carbon preforms. The kinetics of unidirectional infiltration of silicon melt intomicroporous carbon preforms as a function of pore morphology and melt temperature isinvestigated in this paper. Qualitative agreement between experimental data and a mathematicalmodel for capillarity-driven fluid flow through cylindrical pores is demonstrated. Experimentalevidence of high parametric sensitivity is also presented. A simplified model relating fluid flow,transport, and reaction phenomena is formulated to interpret experimental evidence of poreclosing and free silicon entrapment. A robust numerical formulation is also described.
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