高温下平纹编织碳/酚醛复合材料等效热导率的理论预测及分析

The study of the thermal properties of plain-woven carbon/phenolic composites at high temperatures is a challenge.A prediction model of thermal conductivity of plain-woven carbon/phenolic composites was established by combining the three-phase periodic matrix with existing two-phase composite material models based on the microstructural evolution and pyrolysis mechanisms of materials.Taking the porosity of phenolic matrix, the volume fraction of reinforced carbon fiber and temperature into account comprehensively, the dynamic response of thermal conductivity of phenolic and carbon fiber materials, carbon yarn based on microscopic characteristic volume unit and plain-woven carbon/phenolic composites based on mesoscopic characteristic volume unit at high temperature was studied, and the anisotropy of thermal conductivity of materials was analyzed.With the increase of yarn content, the thermal conductivity of carbon/phenolic composites both parallel and vertical to woven surfaces can be increased, and the thermal conductivity of composites parallel to woven surface is 4 ~ 10 times larger than that vertical to woven surface.The model can be used to predict the equivalent thermal conductivity of phenolic materials and carbon fiber materials, carbon yarn and plain fabric composites at high temperature.