采用高速气流冲击式粉体表面改性装置 Hybridization制备了 BN包覆 Ti B2 复合粉末 ,对包覆工艺参数进行了分析并得出了较适宜的包覆条件。用 JSM- 5 6 10 L V型扫描电子显微镜和 H- 6 0 0 STEM/ EDS型透射电子显微镜对包覆体的显微结构进行研究。结果表明 ,包覆时间、转速、Ti B2 与 BN的粒径比、原料预处理等均对包覆效果有显著影响 ;经球形化处理的 Ti B2 粉末与 BN预混合后再进行包覆处理 ,可以得到表面光滑、包覆致密、球形化效果显著的复合粉末。

Fabrication of TiB_2 Composite Powders Coated with h-BN by High Speed Airflow Impact ZHOU Ting-ting 1, FENG Cai-mei 2 (1.Department of Computer Application,Shenzhen Institute of Information Technology,Shenzhen 518029, China; 2.State Key Lab of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070,China)The TiB 2 composite powders coated with BN were fabricated by hybridization system. The equipment makes use of high-speed airflow impact to achieve powder surface modification. Parameters of coating were analyzed and the most appropriate condition was summarized. Scan-electron microscope of JSM-5610LV and transmission-electron microscope of H-600STEM/EDS were used to study the microstructure characteristics of coated powders. Results show that coating time、 rotate speed、 granularity ratio of TiB 2 and BN、 materials disposal in advance,etc would influence coating results greatly. Disposing TiB 2 powders and mixing raw materials beforehand, then doing coating under the most appropriate condition, the composite powders with glazed surface can be obtained.technique of high speed airflow impact; coating; TiB 2/BN composite powders