Finite Element Calculation Of Effective Thermal Conductivity Of Three-dimensional Interpenetrating Network Structure Composites

The metal-ceramic composites with three-dimensional?3D?interpenetrating network structure can retain the excellent performance of each composition to the utmost,and this makes that the composites have excellent high-temperature mechanical,high-temperature resistance,high-temperature oxidation resistance,electrical and thermal conductivity properties,etc.What's more,this excellent properties broad application prospects in electronic packaging materials,space shuttle engine blades,rocket fire hose linings and so on.Therefore,this paper aims at studying the effective thermal conductivity of 3D interpenetrating network structure composites by finite element method.The main research contents and conclusions are as follows:?1?Random sequential adsorption algorithm was used to random particle model with different volume spherical particle,following with Finite Element Method?FEM?to predict the effective thermal conductivity under the corresponding particle volume content,and then the results were compared with Rayleigh model and Maxwell-Eucken model calculation values,deviation increased with the increase of particle volume content,from-8.1%to 0.4%;?2?When the volume content of particle was higher than 15%,the network structure formed because of the aggregation among particle was considered,as a simplified model was developed by structural simplification and also followed with FEM to predict the effective thermal conductivity,the prediction results were more consistent with results based on random particle model than the Rayleigh model and the Maxwell-Eucken model under the corresponding volume content,with a deviation of 0.4%-1.2%;?3?The 3D interpenetrating network structure MoSi₂-RSiC composites with RSiC volume content of 82.6%was used as the research object,as a Microstructure-based model based on real microstructure of the composites was reconstructed by series slicing technology and used to predict effective thermal conductivity of the composites from room temperature to 1600K by FEM.At the same time,the thermal conductivity of the composite under the corresponding temperature range was also obtained by laser method,and used to well verify the the reliability of the numerical results,and the deviation was between 6.8%and 9.6%;?4?Based on the Simplified model,the temperature field distribution in the composites with 3D interpenetrating network structure is studied,and the high temperature region is mainly concentrated at the interface between two phases,which laid a foundation for the study of structure-thermal coupling analysis.