仿生制备多孔ZrC/C复合陶瓷材料

以碳化后的梧桐木块作为碳模板,采用金属锆作为锆源,在KCl和KF的混合熔盐体系中制备了多孔ZrC/C复合陶瓷材料。研究了不同碳化温度对碳模板的显微形貌、显气孔率和体积密度的影响。并采用X射线光电子能谱(XPS)、傅里叶变换红外光谱(FTIR)、X射线衍射仪(XRD)和扫描电子显微镜(SEM)表征了梧桐木的碳化过程以及复合材料的物相组成和显微形貌。结果表明:梧桐木的碳化分为有机物的热分解和石墨化两个过程;碳化后的梧桐木保留了多孔的特征结构,随着碳化温度的升高,碳模板显气孔率变大,体积密度减小;反应时间的延长有利于增强ZrC层与碳模板基体表面的结合力;KF的加入量需要严格控制,过量的KF会破坏复合材料的结构。

Biomimetic Synthesis of Porous ZrC/C Composite Ceramic Materials

Porous ZrC/C composite ceramic materials were prepared in a KCl-KF molten salt reaction medium,using the car-bonized platane wood as carbon source and Zr as metal source.Systematically investigations of the C templates on microstructures, apparent porosities and bulk densities in different carbonization temperatures were carried out.The carbonize procedure of platane wood and the phase compositions and morphological structures of the composite materials were characterized by X-ray photoelectron spectroscopy (XPS),fourier transform infrared (FTIR),X-ray diffraction (XRD)and scanning electron microscopy (SEM).The re-sults showed that the carbonization of platane wood included the two processes of organic matter decomposition and graphitization. The porous structure of platane wood was well retained in the resulting C templates.The apparent porosities of C templates increased and the bulk densities decreased with the increase of carbonization temperature.The increase of reaction time can strengthen the bin-ding force of ZrC layer and C template.The amount of KF requires strict control because excess KF can damage the structure of the composite material.