粒状增强体种类对沥青基炭复合材料性能的影响(英文)

Effect of granular reinforcements on the properties of pitch-based carbon composites

采用普通液压机及新型的模压半炭化成型工艺,在大气环境下制备出了高密度、低成本、应用广的三种焦炭(冶金焦、沥青焦Ⅰ和沥青焦Ⅱ)颗粒增强的沥青基炭复合材料(简称PCCs)。通过对PCCs材料先后进行快速焙烧处理,沥青浸渍-炭化致密化处理和高温石墨化(2 373K)处理,制得了PCC材料的焙烧样品、致密化样品和石墨化样品。通过力学性能试验,SEM和XRD等方法,研究了增强体焦炭颗粒的种类对沥青基炭复合材料的体积密度和抗压强度的影响。结果表明:PCCs材料抗压强度的高低,除了与其体积密度相关外,还与其所采用的增强体焦炭颗粒的耐压强度、微观结构和表面状态有密切的关系。焦炭颗粒的耐压强度愈高、表面越粗糙、开孔孔隙越多,其对沥青基炭复合材料的增强作用也就越显著。无论PCCs材料是焙烧样品、致密化样品、还是石墨化样品,用磨碎冶金焦制备的PCCs材料的三种样品的抗压强度最大,用沥青焦Ⅱ制备的PCCs材料的次之,用沥青焦Ⅰ制备的CRPCC材料的最小。粒状增强体的种类对CRPCC材料的力学性能不仅具有非常重要的影响,而且其强度也具有一定的遗传性。

Pitch-based carbon composites （PCCs） reinforced by three granular cokes, metallurgical coke, No. 1 pitch coke and No. 2 pitch coke, were prepared under an air atmosphere using a hydraulic press and new mold pressing and semi-carbonization shaping technology. The as-fabricated PCCs were treated in turn by quick baking, one-time densification and graphitization at 2373 K, and three corresponding samples were obtained. The effect of the type of granular coke used as reinforcement on the volume density and mechanical properties of the PCCs was studied by a materials testing machine, SEM, and XRD. Results indicate that the compressive strength of the PCCs is closely related to the surface morphology, microstructure, and compressive strength of the granular cokes. A higher compressive strength, coarser surface and more open porosity of granular cokes induce higher reinforcement to the composites. The PCCs can be obtained through baking, densification, and graphitization. The compressive strength of the PCCs fabricated using metallurgical cokes is the highest with those from No. 2 pitch coke in the middle and those from No. 1 pitch coke the lowest. The granular cokes not only greatly influence the mechanical properties of the PCCs, but also, to some extent, pass their original strength to their descendants.