• 文献标题:   In-situ graphene platelets formation and its suppression during reactive spark plasma sintering of boron carbide/titanium diboride composites
  • 文献类型:   Article
  • 作  者:   UNSAL H, GRASSO S, KOVALCIKOVA A, HANZEL O, TATARKOVA M, DLOUHY I, TATARKO P
  • 作者关键词:   boron carbide, titanium diboride, graphene platelet, spark plasma sintering, reactive sintering
  • 出版物名称:   JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
  • ISSN:   0955-2219 EI 1873-619X
  • 通讯作者地址:  
  • 被引频次:   9
  • DOI:   10.1016/j.jeurceramsoc.2021.06.053 EA AUG 2021
  • 出版年:   2021

▎ 摘  要

Boron carbide composites with 10 vol.% TiB2 were prepared by reactive sintering of B4C, TiO2, and carbon black powder mixture at the temperature of 1800 degrees C, under a pressure of 70 MPa in a vacuum. The combined effects of electric current and in-situ reactions led to a significant overheating of the central part of the sample, while no overheating was observed for hot press and non-reactive SPS processes. A lower electrical resistivity of TiB2 produced a significant Joule heating of boron carbide, leading to its partial decomposition to form gaseous boron and graphene platelets. Homogenous, fully dense and graphene-free samples were obtained when employing an insulating Al2O3 paper during reactive SPS. A short dwell time (30 s after a degassing step of 6 min) and the uniform distribution of fine TiB2 grains were the main advantages of isolated SPS over the reactive hot press and SPS processes, respectively.