基于分形原理的双连续相复合材料成形过程传热传质机理研究

Focusing on the research of the three-dimensional network of the ceramic/metal composite (C4), the project is planning to investigate the infiltration flow, heat and mass transfer of solidification in the process of C4 composite molding from the perspective of engineering thermal physics.The SEM images and the thermal field analysis of the forming processes of the composite materials will be completed through the experiment reaearch. Furthermore, the two-dimensional and three-dimensional porous structures will be obtained by using mathematical statistics. Through the image anslysis theory, the mathematical characteristics will be obtained such as porosity, pore diameter, correlation. Then the morphological structure of porous ceramics will be described based on the fractal theory, and it could provide theoretical basis for optimal control in the molding process.The Lattice-Boltzmann method is used to simulate liquid alloy seepage process with a pore scale. For a porous ceramic with a REV scale, this method is also used to simulate the heat and mass transfer occurred in the alloy solidification process. And the theoretical analysis will be conducted to investigate the infiltration process and relevant influencing factors within a porous ceramic for a liquid Al alloy under the effect of a phase changing process and interfacial chemical reactions. Through analyzing the transmission mechanism of the composite molding process in the three-dimensional network, the project is purposed to provide a theoretical guarantee for the research of composite material properties and microstructure from the angle of the materials science.

以陶瓷/金属三维网络复合材料（Co-continuous Ceramic Composites,C4材料）为研究对象，从工程热物理的角度研究其成型过程中的浸渗流动、凝固传热传质等问题。通过实验研究完成SEM照片及复合材料成形过程中的热流场分析；采用数学统计方法构造二维和三维随机多孔结构，运用图像分析理论得到孔隙率、孔径、相关性等数学特征，进而应用分形理论描述多孔陶瓷的形态结构，为其成型工艺优化控制提供理论依据；利用LBM方法模拟孔隙尺度内液态合金的渗流规律以及表征体元（REV）尺度上合金在多孔陶瓷内凝固过程中的传热传质规律，对液态Al合金在界面化学反应作用下和有相变变化过程中多孔陶瓷内的浸渗过程以及影响因素进行理论分析，综合各种研究手段分析三维网络复合材料成型过程中的传输机理，为从材料学角度对复合材料性能和微观组织研究结果提供理论基础。

以陶瓷/金属三维网络复合材料（Co-continuous Ceramic Composites,C4材料）为研究对象，从工程热物理的角度研究其成型过程中的浸渗流动、凝固传热传质等问题。采用数学统计方法构造二维和三维随机多孔结构，运用图像分析理论得到孔隙率、孔径、相关性等数学特征，进而应用分形理论描述多孔陶瓷的形态结构，为其成型工艺优化控制提供理论依据；利用LBM方法模拟孔隙尺度内液态合金的渗流规律以及表征体元（REV）尺度上合金在多孔陶瓷内凝固过程中的传热传质规律，综合各种研究手段分析三维网络复合材料成型过程中的传输机理，为从材料学角度对复合材料性能和微观组织研究结果提供理论基础。本课题按照计划书内容完成基本实验平台的搭建，搭建三维网络复合材料的浸渗和凝固实验平台，可以实现测量、记录复合材料凝固成形过程中的温度场和浸渗位置变化；利用高速摄像机对复合材料凝固过程与成形过程中的热流场开展实验研究；建立LBM大黏度比模型对基于分形理论的多孔陶瓷浸渗和凝固过程进行研究；完成复合材料浸渗凝固过程的LBM模拟研究并对界面化学反应浸渗过程进行理论分析。采用修正的LBM多组分伪势模型模拟了液态法制备金属基复合材料过程中多孔介质内的浸渗过程，研究了黏度比、壁面润湿性、雷诺数、孔隙率以及不同分形结构对浸渗过程的影响等。