ZrB_2／C复合材料的性能及微观结构研究

Properties and Microstructure of ZrB_2/C Composites

采用热压工艺制备了ZrB2／C复合材料,考察了ZrB2掺杂量对材料抗弯强度、热导率、电阻率的影响以及微观结构的变化．结果表明:随ZrB2含量增加,材料抗弯强度和热导率不断升高。在掺杂量为10％时,抗弯强度达到最大值131MPa,热导率达到161W／m·K的最大值,此后,抗弯强度和热导率随掺杂量增加而降低．然而,材料的电阻率随ZrB2含量的增加不断下降．微观结构分析表明,随着ZrB2掺杂量增加,材料的石墨化度和微晶尺寸增大,晶面层间距减小．材料的微观结构强烈地影响着材料的力学、导电、导热等宏观性能．

ZrB2/C composites were prepared by a hot-pressing method. The influence of dopants on the flexural strength, thermal conductivity, electrical resistivity and microstructure of these composites was investigated. Results show that the flexural strength and thermal conductivity increase with increasing ZrB2 content up to a maximum of 131MPa and 161W/m·K at 10% addition, respectively. But the electrical resistivity reduces rapidly with increasing the concentration of ZrB2. Correlations between the content of dopant and properties and microstructure of ZrB2/C composites were also discussed.