The Microstructures and Properties of Carbon and Graphite Materials Prepared from Mesocarbon Microbeads by Different Molding Methods

Abstract:

Mesocarbon microbeads (MCMBs) are the prominent precursors for high-strength and high-density carbon and graphite materials (CGM). The microstructures and properties of CGM prepared by different compaction techniques using raw powders or pelleted powders of MCMBs with low content of β-resins was investigated in the present study. The green blocks by one-step uniaxial compaction at 230MPa were carbonized at 1200°C, forming carbon blocks with density of 1.84g/cm³ and bending strength of 76.9MPa. After graphitizing at 2700°C the carbon blocks are with density of 1.91g/cm³ and flexural strength of 70.5MPa. One-step cold isotropic pressing can improve the moldability of green blocks and increase open porosity of graphite blocks to 12.64vol%, with density of 1.87g/cm³. The green blocks with no cracks prepared by multistep cold isotropic pressing exhibit density of 1.84g/cm³ and bending strength of 81.7MPa. However, the flexural strength of these carbon and graphite artifacts decreased by 11.6~32.0MPa with comparison to the ones directly prepared from MCMBs.

• Periodical: Materials Science Forum (Volume 849)
• Pages: 831-837
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.849.831
• Online since: March 2016
• Authors: Zu Qiong Zhang, Hong Wan, Xing Yu Cheng
• Keywords: Bending Strength, Cold Isotropic Pressing, Mesocarbon Microbeads, Uniaxial Compaction

References

[1] Li Fei, Ni Hongjun, Wang Jun, Gelcasting of aqueous mesocarbon microbead suspension, Carbon. 42(2004) 2989-2995.

DOI: 10.1016/j.carbon.2004.07.012

[2] Lü Yonggen, Ling Licheng, Liu Lang, Zhang Bijiang, The effects of primary PI in coal tar on the preparation of mesocarbon Microbeads, New Carbon Materials. 13(1998) 38-42.

[3] Shen Z M, New carbon materials, Beijing: Chemical Industry Press. 2003: 98-133.

[4] Yoon S H, Park Y D, Mochida I, Preparation of carbonaceous spheres from suspensions of pitch materials, Carbon. 30(1992): 781-786.

DOI: 10.1016/0008-6223(92)90162-p

[5] Zhen Li, Effect of catalytic heat treatment on the electrochemical performance of mescocarbon microbeads as anode material for Lithium-ion batteries, Beijing: Beijing University of Chemical Technology, (2007).

[6] Ai Yanling, Li Tiehu, Ji Yongbin, Comparing properties of Activated Carbon Prepared by Microwave Heating Method with Those Prepared by Conventional Heating Method, Journal of Northwestern Polytechnical Unversity. 27(2009): 527-531.

[7] Li Min, Wen Guang-wu, Current research status of preparation of carbon/graphite materials with high density and strength from mesocarbon microbeads, Carbon Techniques. 25(2006): 37-41.

[8] Martinez-Escandell M, Carreira P, Rodriguez-Valero M A, et al, Self-sintering of carbon mesophase powders: effect of extraction washing with solvents, Carbon. 37(1999): 1662-1665.

DOI: 10.1016/s0008-6223(99)00169-4

[9] Gao Yan, Song Huai-he, Chen Xiao-hong, The influence of oxidative treatment on the performance of carbon blocks from self-sintering pitch-based mesocarbon microbeads, New Carbon Materials. 17(2002): 13-17.

[10] Chung D D L, The influences of calcination of mesocarbon microbeads on the properties of bulk carbon materials, New Carbon Materials. 2(1994): 49-50.

[11] Y. Gao, H.H. Sing, X.H. Chen, Y.L. Mao, X.L. Liu, Influences of β-resin content of mesocarbon microbeads on the properties of high density isotropic carbon, Chin. J. Mater. Res. 16 (2002): 205-209.

[12] Yongzhong Song, GengtaiZhai, et al, Carbon/graphite seal materials prepared from mesocarbon microbeads, D. Shanxi: Institute of Coal Chemistry, Chinese Academy Sciences, 42(2004): 1427-1433.

DOI: 10.1016/j.carbon.2003.12.037

[13] Lu Xiu-rong, Wang Cheng-yang, Fan qi-ming, The influence of characteristics of ultra-fine MCMB powders and molding conditions on the properties of sintered bodies, New Carbon Materials. 19(2004): 109-113.

[14] Hoffimann WR, Huttinger KJ, Sintering of powders of poly-aromatic mesophase to high-strengh isotropic carbon-I. Influence of the raw materials and sintering condition on the properties of carbon materials, Carbon. 32(1994): 103-1087.

DOI: 10.1016/0008-6223(94)90218-6

[15] Rosales CG, Ordas N, Oyrzabal E, et al, Improvement of the thermo-mechanical properties of fine grain graphite by doping with different carbides, Journal of Nuclear Materials. 307-311 (2002): 1282-1288.

DOI: 10.1016/s0022-3115(02)00960-1