焦炭颗粒/热解炭复合材料的制备与压缩性能研究

Fabrication and compressive properties of coke particles/pycarbon composites

分别以LJ1、LJ2、YJ、ZJ 4种焦炭颗粒作为增强体,CVD炭作为基体,利用TCVI设备制备出了焦炭颗粒增强热解炭基(焦炭颗粒/热解炭)复合材料。并从其力学性能着手,使用金相显微镜分析其显微结构,采用扫描电镜观察其断口微观形貌,并结合载荷-位移曲线综合分析其断裂方式及机理。结果表明:4种焦炭颗粒/热解炭复合材料中,LJ1和ZJ焦炭颗粒沉积前后密度与质量变化最大,其质量分别增加57.4%和64.3%;焦炭颗粒/热解炭复合材料微观组织结构为各向异性;LJ2焦炭颗粒/热解炭复合材料轴向和径向的压缩强度分别为203.7 MPa和176.3 MPa,在4种焦炭颗粒/热解炭复合材料中强度最高;4种焦炭颗粒/热解炭复合材料压缩断裂方式为脆性断裂,LJ2焦炭颗粒/热解炭复合材料和YJ焦炭颗粒/热解炭复合材料主要是因其内部焦炭颗粒孔洞的应力集中造成断裂,LJ1焦炭颗粒/热解炭复合材料和ZJ焦炭颗粒/热解炭复合材料主要沿其焦炭颗粒的层片断裂。

The pitch cokes （L J1, LJ2）, petroleum coke （Z J）, and metallurgical coke （YJ）were used as reinforcement dividedly, and the coke/pycarbon （pyc） composites were fabricated by thermal chemical vapor infiltration （TCVI） in this paper. The microstructure and compressive properties of coke/pyc composites were characterized and analyzed. Results show that the mass and density changes of LJ1/pyc and ZJ/pyc composites before and after TCVI were maximal; the compressive strength of LJ2/pyc composite was the high- est, and mainly decided by the volume fraction, apparent performance and micrestructure of cokes; all the four coke/pyc composites broke in brittle style.