鳞片石墨/中间相沥青基石墨化泡沫炭的结构与性能研究

Study on structure and properties of mesophase-pitchderived graphitized foam modified by flake graphite

以鳞片石墨/AR中间相沥青为原料,通过高温自发泡法制备泡沫炭生料,经炭化、石墨化处理获得炭化泡沫炭和石墨化泡沫炭。采用TG-DTG、IR、SEM、XRD等方法研究了鳞片石墨含量对石墨化后泡沫炭的显微结构及其物理性能的影响。实验表明,随着鳞片石墨含量的增加,泡沫炭的孔径分布变得不均匀,孔壁及通孔处微裂纹明显减少且变短,韧带变宽,通孔增多,石墨化泡沫炭的抗压强度增大。鳞片石墨含量为10%时,石墨化泡沫炭的热导率达到最大值,为71.5 W/(m·K),抗压强度为2.19 MPa。

Graphitized carbon foam was obtained through carbonization and graphitization of green foam formed by AR mesophase pitch mixed with flake graphite in a high pressure and temperature reactor. The effects of flake graphite content on microstructure and physical property of the obtained carbon foams were studied by TG, IR, SEM and XRD in detail. The results show that, with the increase of the flake graphite content, carbon foam exhibited wider ligament, fewer micro-cracks were formed in the cell wall of the carbon foam, and the pore size distribution of the carbon foam became less uniform. Meanwhile, the graphitized carbon foam possessed high mechanical strength and exceptional thermal conductivity after adding the flake graphite. The thermal conductivity of graphitized carbon foam reached 71.5 W/（m·K）, and its compressive strength increased to 2.19 MPa with the addition of 10% flake graphite.