摘要
用粉末冶金真空烧结法制备了超细晶粒碳氮化钛[Ti(C,N)]基金属陶瓷。研究了原始粉末粒径对Ti(C,N)基金属陶瓷微观结构和力学性能的影响。结果表明:在化学成分相同的条件下,晶粒细化使材料的Vickers硬度和抗弯强度上升,但断裂韧性有所下降。在超细晶粒Ti(C,N)基金属陶瓷微观组织中出现了一种新型的白芯/灰壳结构和一种特殊化合物(Ni2Mo2.5W1.3)Cx。初步研究表明:由于原始粉末粒径微小,促进了扩散反应因而生成了这种芯/壳结构。芯/壳结构有利于提高材料的抗弯强度和断裂韧性。(Ni2Mo2.5W1.3)Cx有利于提高材料的Vickers硬度,但是降低了Ti(C,N)基金属陶瓷的抗弯强度和断裂韧性。
Ultra-free grain Ti（C, N）-based cermets were manufactured by the powder metallurgy vacuum sintering technology. Effect of starting powder size on microstructure and mechanical properties of Ti（C, N）-based cermets were studied. The experimental results indicate that under conditions of the same chemical composition, the Vickers hardness and bending strength of Ti（C, N）-based cermets increase with the decrease of grain size in cermet, while its fracture toughness shows an opposite trend. A new compound that can be denoted as （Ni2Mo2.5W1.3）Cx existed in the microstructure, and a new kind of core/rim structure with a white core and gray rim was also found in the cermets. This new core/rim structure was formed because the reaction diffusion happened easily due to the fine size of the raw powder. It is believed that this new core/rim structure helps to improve the bending strength of the material. The presence of （Ni2Mo2.5W1.3）Cx phase is beneficial to the Vickers hardness, but harmful to the bending strength and fracture toughness of Ti（C, N）-based cermets.
出处
《硅酸盐学报》
EI
CAS
CSCD
北大核心
2007年第6期725-730,共6页
Journal of The Chinese Ceramic Society
基金
"九五"国家科技攻关计划(99D049)
教育部留学回国人员科研启动基金(050202B2)资助项目
关键词
超细晶粒
碳氮化钛基金属陶瓷
微观结构
力学性能
ultra-free grain
titanium carbonitride based cermet
microstructure
mechanical property
