Synthesis Mechanism of TiB2-TiC-Ni Composites Produced by Combustion Reaction of Ti-Ni-B4C System in the High-Gravity Field

4th Annual International Workshop on Materials Science and Engineering

Zhang, Jing^1 ; Pan, Chuanzeng^1 ; Zhang, Yifei^1 ; Cheng, Zhaogang^1

Army Engineering University, 97 Heping west road, Shijiazhuang

050003, China^1

关键词: Boron and carbons;    Combustion reactions;    Fine-grained microstructure;    High-gravity field;    Intermediate product;    Microstructural investigation;    Reaction process;    Synthesis mechanism;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/381/1/012055/pdf
DOI  :  10.1088/1757-899X/381/1/012055

来源: IOP

【 摘 要 】

TiB2-TiC-Ni composites were fabricated through combustion reaction of Ti-Ni-B4C in a high gravity field. TiB2-TiC-Ni composites were pore-free with darker TiB2 phases and the brighter TiC easily distinguishable. The microstructure consisted of TiB2 platelets with an aspect ratio of 2 and equiaxed TiC grains. The reaction process was controlled by the high-gravity field, which was considered to accelerate decomposition of B4C and diffusion of boron and carbon atoms. The melting Ni and Ti increased the diffusion path for boron and carbon atoms, thereby promoting the reaction process. The rapid cooling of Ti-B-C-Ni full-liquid intermediate products immediately was expected following the reaction of Ti and B4C, which was responsible for fine-grained microstructure. The microstructural investigations have confirmed the role of high gravity field and Ni dilute as promoters of densification of the final products and grain refinement in this experimental.