WANG Xiaonan 1,2, TAO Qiang 1, ZUO Bin 2, ZHU Pinwen 1
(1. State Key Laboratory of Superhard Materials, College of Physics, Jilin University, Changchun 130012, Jilin, China; 2. Key Laboratory of Functional Materials Physics and Chemistry of the Ministry of Education,Jilin Normal University, Changchun 130103, Jilin, China)
Abstract: B4C-TiB2 composite not only possess the high hardness and low density of B4C, but also exhibits the high toughness and conductivity of TiB2, which has great advantages as composite ceramics received widespread attentions. Obtaining high toughness and high hardness simultaneously for B4C-TiB2 composite has always been an urgent need and a great challenge. In recent years, B4C-TiB2 composite ceramics have been widely and extensively studied. In this paper, the progress in the development of B4C-TiB2 composite ceramics is reviewed, with focus on key factors, including relative density, content of the toughening phase, grain size and the third phase additive. It is concluded that high density and appropriate content of toughening phase (≤15%) are the necessary conditions for obtaining B4C-TiB2 composite ceramics with balanced hardness and toughness. Meanwhile, grain refinement can promote the enhancement of grain boundary between B4C and TiB2 and increase the intergranular fracture mode, which are conducive to the improvement of hardness and toughness. In addition, the properties of B4C-TiB2 composite can be further enhanced with the addition of third phase by increasing the density and modifying the microstructure.
Key words: B4C-TiB2; composite ceramic; sintering method; mechanical property