MICROMECHANICAL MODELLING OF CARBON/CARBON COMPOSITES WITH PORES

摘要

This paper presents a procedure to model carbon/carbon composites containing pores of irregular shapes. Closed form expressions for contributions of fibres and pores into effective elastic moduli are provided. The procedure is applied to predict the transverse elastic properties of unidirectional carbon/carbon composites (carbon fibres in pyrolytic carbon matrix) densified by chemical vapor infiltration. Infiltration treatment results in formation of irregularly shaped pores randomly oriented in the plane perpendicular to the direction of fibre (transverse plane). These pores are analyzed using numerical conformal mapping technique, and their contribution to the effective elastic properties is expressed in terms of the cavity compliance contribution tensor. Components of this tensor are found for a variety of typical pore shapes.